From 38f7c9726eada3c5de6f698d3bb67421f12a10cb Mon Sep 17 00:00:00 2001
From: Audiolib <audiolib@setup>
Date: Tue, 26 May 2026 18:22:44 +0200
Subject: [PATCH] =?UTF-8?q?Extract=20AudioEngine=20=E2=80=94=20fix=20root?=
 =?UTF-8?q?=20cause=20of=20broken=20playback?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

ROOT CAUSE: AudioPlayer was the only component holding the <audio>
element, and it was only mounted when expanded=true. The MiniPlayer
(default state after Play) had no audio element at all. So clicking
Play set the store state but no audio was ever loaded or played.

Fix: New AudioEngine component holds the single <audio> element and
all playback logic. Mounted globally in App.tsx whenever an item is
loaded — independent of MiniPlayer/AudioPlayer UI state.

Store: New seekRequest (counter-based) lets external UI request seeks
without direct audio element access. New playerError surfaces errors
across MiniPlayer (red progress bar) and AudioPlayer (banner).

AudioPlayer + MiniPlayer reduced to pure UI components that interact
through the store. They can mount/unmount freely without affecting
playback.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 frontend/src/App.tsx                          |   4 +
 .../src/components/player/AudioEngine.tsx     | 229 ++++++++++++++++++
 .../src/components/player/AudioPlayer.tsx     | 219 ++---------------
 frontend/src/components/player/MiniPlayer.tsx |   8 +-
 frontend/src/store/playerStore.ts             |  19 +-
 5 files changed, 278 insertions(+), 201 deletions(-)
 create mode 100644 frontend/src/components/player/AudioEngine.tsx

diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 4c9735a..8f862f5 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -4,6 +4,7 @@ import { useAuthStore } from './store/authStore'
 import { usePlayerStore } from './store/playerStore'
 import Layout from './components/common/Layout'
 import AudioPlayer from './components/player/AudioPlayer'
+import AudioEngine from './components/player/AudioEngine'
 import Login from './pages/Login'
 import Setup from './pages/Setup'
 import Library from './pages/Library'
@@ -21,6 +22,7 @@ function AppRoutes() {
   const { user, loadAuth } = useAuthStore()
   const { libraries } = useAuthStore()
   const { expanded, setExpanded } = usePlayerStore()
+  const item = usePlayerStore((s) => s.item)
   const [setupNeeded, setSetupNeeded] = useState<boolean | null>(null)
 
   useEffect(() => {
@@ -64,6 +66,8 @@ function AppRoutes() {
         />
       </Routes>
 
+      {item && <AudioEngine />}
+
       {expanded && (
         <div className="fixed inset-0 bg-background z-50 overflow-y-auto">
           <AudioPlayer />
diff --git a/frontend/src/components/player/AudioEngine.tsx b/frontend/src/components/player/AudioEngine.tsx
new file mode 100644
index 0000000..b857864
--- /dev/null
+++ b/frontend/src/components/player/AudioEngine.tsx
@@ -0,0 +1,229 @@
+import { useEffect, useRef } from 'react'
+import { usePlayerStore } from '../../store/playerStore'
+
+interface Track {
+  index: number
+  startOffset: number
+  duration: number
+  contentUrl: string
+  mimeType: string
+}
+
+function findTrackForTime(tracks: Track[], time: number): number {
+  for (let i = tracks.length - 1; i >= 0; i--) {
+    if (time >= (tracks[i].startOffset || 0)) return i
+  }
+  return 0
+}
+
+/**
+ * Globale Audio-Engine. Wird immer gemountet, sobald ein item geladen ist.
+ * Hält das einzige <audio>-Element der App, lauscht auf Store-Änderungen
+ * (seekRequest, isPlaying, playbackRate, volume) und schreibt currentTime
+ * zurück in den Store.
+ */
+export default function AudioEngine() {
+  const session = usePlayerStore((s) => s.session)
+  const isPlaying = usePlayerStore((s) => s.isPlaying)
+  const playbackRate = usePlayerStore((s) => s.playbackRate)
+  const volume = usePlayerStore((s) => s.volume)
+  const seekRequest = usePlayerStore((s) => s.seekRequest)
+  const setCurrentTime = usePlayerStore((s) => s.setCurrentTime)
+  const setPlaying = usePlayerStore((s) => s.setPlaying)
+  const setPlayerError = usePlayerStore((s) => s.setPlayerError)
+  const syncProgress = usePlayerStore((s) => s.syncProgress)
+
+  const audioRef = useRef<HTMLAudioElement | null>(null)
+  const currentTrackIdx = useRef(0)
+  const pendingSeek = useRef<number | null>(null)
+  const lastSeekCounter = useRef(0)
+  const isPlayingRef = useRef(false)
+
+  useEffect(() => { isPlayingRef.current = isPlaying }, [isPlaying])
+
+  const tracks: Track[] = session?.audioTracks || []
+
+  // Audio-Element nur einmal anlegen
+  useEffect(() => {
+    const audio = new Audio()
+    audio.preload = 'auto'
+    audioRef.current = audio
+
+    const onTimeUpdate = () => {
+      const a = audioRef.current
+      if (!a) return
+      const tracksNow = usePlayerStore.getState().session?.audioTracks || []
+      const offset = tracksNow[currentTrackIdx.current]?.startOffset || 0
+      setCurrentTime(offset + a.currentTime)
+    }
+    const onLoadedMetadata = () => {
+      const a = audioRef.current
+      if (!a) return
+      console.log('[Engine] loadedmetadata', {
+        trackIdx: currentTrackIdx.current,
+        duration: a.duration,
+        pendingSeek: pendingSeek.current,
+      })
+      if (pendingSeek.current !== null) {
+        try { a.currentTime = pendingSeek.current } catch (e) { console.warn('seek failed', e) }
+        pendingSeek.current = null
+      }
+    }
+    const onCanPlay = () => {
+      if (pendingSeek.current !== null && audioRef.current) {
+        try { audioRef.current.currentTime = pendingSeek.current } catch {}
+        pendingSeek.current = null
+      }
+    }
+    const onEnded = () => {
+      const tracksNow = usePlayerStore.getState().session?.audioTracks || []
+      const nextIdx = currentTrackIdx.current + 1
+      console.log('[Engine] ended', { nextIdx, total: tracksNow.length })
+      if (nextIdx < tracksNow.length) {
+        currentTrackIdx.current = nextIdx
+        pendingSeek.current = null
+        const a = audioRef.current!
+        a.src = tracksNow[nextIdx].contentUrl
+        a.load()
+        a.play().catch((e) => {
+          console.warn('[Engine] play() failed:', e)
+          setPlayerError(`Wiedergabe blockiert: ${e?.message || e}`)
+        })
+      } else {
+        setPlaying(false)
+        syncProgress()
+      }
+    }
+    const onError = () => {
+      const a = audioRef.current
+      const err = a?.error
+      const codeMap: Record<number, string> = {
+        1: 'MEDIA_ERR_ABORTED — Abruf abgebrochen',
+        2: 'MEDIA_ERR_NETWORK — Netzwerkfehler beim Laden',
+        3: 'MEDIA_ERR_DECODE — Format nicht dekodierbar',
+        4: 'MEDIA_ERR_SRC_NOT_SUPPORTED — Quelle nicht unterstützt (404/Format/MIME)',
+      }
+      const msg = err
+        ? `${codeMap[err.code] || `Code ${err.code}`}${err.message ? ': ' + err.message : ''}`
+        : 'Unbekannter Audio-Fehler'
+      console.error('[Engine] audio error', {
+        code: err?.code,
+        message: err?.message,
+        src: a?.src,
+        networkState: a?.networkState,
+        readyState: a?.readyState,
+      })
+      setPlayerError(msg)
+    }
+
+    audio.addEventListener('timeupdate', onTimeUpdate)
+    audio.addEventListener('loadedmetadata', onLoadedMetadata)
+    audio.addEventListener('canplay', onCanPlay)
+    audio.addEventListener('ended', onEnded)
+    audio.addEventListener('error', onError)
+
+    return () => {
+      audio.removeEventListener('timeupdate', onTimeUpdate)
+      audio.removeEventListener('loadedmetadata', onLoadedMetadata)
+      audio.removeEventListener('canplay', onCanPlay)
+      audio.removeEventListener('ended', onEnded)
+      audio.removeEventListener('error', onError)
+      audio.pause()
+      audio.removeAttribute('src')
+      audio.load()
+      audioRef.current = null
+    }
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [])
+
+  // Bei neuer Session: Track laden
+  useEffect(() => {
+    const audio = audioRef.current
+    if (!audio || !session || !tracks.length) return
+
+    const startTime = session.currentTime || 0
+    const startIdx = findTrackForTime(tracks, startTime)
+    const timeInTrack = startTime - (tracks[startIdx]?.startOffset || 0)
+
+    console.log('[Engine] init session', {
+      sessionId: session.id,
+      tracks: tracks.length,
+      duration: session.duration,
+      startTime,
+      startIdx,
+      timeInTrack,
+      url: tracks[startIdx]?.contentUrl,
+    })
+
+    currentTrackIdx.current = startIdx
+    pendingSeek.current = timeInTrack > 0 ? timeInTrack : null
+    setPlayerError(null)
+
+    audio.playbackRate = playbackRate
+    audio.volume = volume
+    audio.src = tracks[startIdx].contentUrl
+    audio.load()
+    audio.play().catch((e) => {
+      console.warn('[Engine] play() failed:', e)
+      setPlayerError(`Wiedergabe blockiert: ${e?.message || e}`)
+    })
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [session?.id])
+
+  // play/pause
+  useEffect(() => {
+    const audio = audioRef.current
+    if (!audio || !audio.src) return
+    if (isPlaying) {
+      audio.play().catch((e) => {
+        console.warn('[Engine] play() failed:', e)
+        setPlayerError(`Wiedergabe blockiert: ${e?.message || e}`)
+      })
+    } else {
+      audio.pause()
+    }
+  }, [isPlaying, setPlayerError])
+
+  // playbackRate
+  useEffect(() => {
+    if (audioRef.current) audioRef.current.playbackRate = playbackRate
+  }, [playbackRate])
+
+  // volume
+  useEffect(() => {
+    if (audioRef.current) audioRef.current.volume = volume
+  }, [volume])
+
+  // seekRequest: extern angefragter Sprung
+  useEffect(() => {
+    if (!seekRequest || seekRequest.counter === lastSeekCounter.current) return
+    lastSeekCounter.current = seekRequest.counter
+
+    const audio = audioRef.current
+    const tracksNow = usePlayerStore.getState().session?.audioTracks || []
+    if (!audio || !tracksNow.length) return
+
+    const t = seekRequest.time
+    const targetIdx = findTrackForTime(tracksNow, t)
+    const timeInTrack = t - (tracksNow[targetIdx]?.startOffset || 0)
+
+    console.log('[Engine] seek', { t, targetIdx, timeInTrack, currentIdx: currentTrackIdx.current })
+
+    if (targetIdx === currentTrackIdx.current) {
+      audio.currentTime = timeInTrack
+    } else {
+      currentTrackIdx.current = targetIdx
+      pendingSeek.current = timeInTrack
+      audio.src = tracksNow[targetIdx].contentUrl
+      audio.load()
+      if (isPlayingRef.current) {
+        audio.play().catch((e) => {
+          console.warn('[Engine] play() failed:', e)
+          setPlayerError(`Wiedergabe blockiert: ${e?.message || e}`)
+        })
+      }
+    }
+  }, [seekRequest, setPlayerError])
+
+  return null
+}
diff --git a/frontend/src/components/player/AudioPlayer.tsx b/frontend/src/components/player/AudioPlayer.tsx
index 44d5365..1e1184f 100644
--- a/frontend/src/components/player/AudioPlayer.tsx
+++ b/frontend/src/components/player/AudioPlayer.tsx
@@ -1,4 +1,4 @@
-import React, { useCallback, useEffect, useRef, useState } from 'react'
+import React, { useEffect, useState } from 'react'
 import {
   Play, Pause, SkipBack, SkipForward, Volume2, VolumeX,
   List, BookmarkPlus, Moon, X, ChevronLeft
@@ -9,25 +9,6 @@ import CoverImage from '../common/CoverImage'
 import { coverUrl } from '../../api/items'
 import ChapterList from './ChapterList'
 
-interface Track {
-  index: number
-  startOffset: number
-  duration: number
-  contentUrl: string
-  mimeType: string
-}
-
-function findTrackForTime(tracks: Track[], time: number): number {
-  for (let i = tracks.length - 1; i >= 0; i--) {
-    if (time >= (tracks[i].startOffset || 0)) return i
-  }
-  return 0
-}
-
-function trackUrl(track: Track): string {
-  return track.contentUrl
-}
-
 export default function AudioPlayer() {
   const session = usePlayerStore((s) => s.session)
   const item = usePlayerStore((s) => s.item)
@@ -39,184 +20,38 @@ export default function AudioPlayer() {
   const chapters = usePlayerStore((s) => s.chapters)
   const sleepTimer = usePlayerStore((s) => s.sleepTimer)
   const sleepTimerActive = usePlayerStore((s) => s.sleepTimerActive)
+  const playerError = usePlayerStore((s) => s.playerError)
   const setPlaying = usePlayerStore((s) => s.setPlaying)
-  const setCurrentTime = usePlayerStore((s) => s.setCurrentTime)
   const setPlaybackRate = usePlayerStore((s) => s.setPlaybackRate)
+  const setVolume = usePlayerStore((s) => s.setVolume)
   const seek = usePlayerStore((s) => s.seek)
   const stop = usePlayerStore((s) => s.stop)
   const setExpanded = usePlayerStore((s) => s.setExpanded)
   const setSleepTimer = usePlayerStore((s) => s.setSleepTimer)
   const cancelSleepTimer = usePlayerStore((s) => s.cancelSleepTimer)
-  const syncProgress = usePlayerStore((s) => s.syncProgress)
-
-  const audioRef = useRef<HTMLAudioElement>(null)
-  const currentTrackIdx = useRef(0)
-  const pendingSeek = useRef<number | null>(null)
 
   const [showChapters, setShowChapters] = useState(false)
   const [showSpeedMenu, setShowSpeedMenu] = useState(false)
   const [showSleepMenu, setShowSleepMenu] = useState(false)
   const [muted, setMuted] = useState(false)
-  const [playerError, setPlayerError] = useState<string | null>(null)
+  const [lastVolume, setLastVolume] = useState(1)
 
-  const tracks: Track[] = session?.audioTracks || []
-
-  // Initialize on session change
   useEffect(() => {
-    if (!session || !audioRef.current || !tracks.length) return
-    const audio = audioRef.current
-
-    const startTime = session.currentTime || 0
-    const startIdx = findTrackForTime(tracks, startTime)
-    const timeInTrack = startTime - (tracks[startIdx]?.startOffset || 0)
-
-    console.log('[Player] init session', {
-      sessionId: session.id,
-      tracks: tracks.length,
-      duration: session.duration,
-      startTime,
-      startIdx,
-      timeInTrack,
-    })
-
-    currentTrackIdx.current = startIdx
-    pendingSeek.current = timeInTrack > 0 ? timeInTrack : null
-    setPlayerError(null)
-
-    audio.preload = 'auto'
-    audio.playbackRate = playbackRate
-    audio.volume = muted ? 0 : volume
-    audio.src = trackUrl(tracks[startIdx])
-    audio.load()
-    audio.play().catch((e) => {
-      console.warn('[Player] play() failed:', e)
-      setPlayerError(`Wiedergabe blockiert: ${e?.message || e}`)
-    })
-
-    return () => {
-      audio.pause()
-      audio.removeAttribute('src')
-      audio.load()
-    }
+    if (muted) setVolume(0)
+    else setVolume(lastVolume)
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [session?.id])
+  }, [muted])
 
-  // Sync isPlaying with audio element
-  useEffect(() => {
-    const audio = audioRef.current
-    if (!audio || !audio.src) return
-    if (isPlaying) audio.play().catch((e) => console.warn('[Player] play() failed:', e))
-    else audio.pause()
-  }, [isPlaying])
-
-  useEffect(() => {
-    if (audioRef.current) audioRef.current.playbackRate = playbackRate
-  }, [playbackRate])
-
-  useEffect(() => {
-    if (audioRef.current) audioRef.current.volume = muted ? 0 : volume
-  }, [volume, muted])
-
-  const seekTo = useCallback((absoluteTime: number) => {
-    const audio = audioRef.current
-    if (!audio || !tracks.length) return
-
-    const lastTrack = tracks[tracks.length - 1]
-    const totalDur = (lastTrack?.startOffset || 0) + (lastTrack?.duration || 0)
-    const clamped = Math.max(0, Math.min(absoluteTime, totalDur || absoluteTime))
-
-    const targetIdx = findTrackForTime(tracks, clamped)
-    const timeInTrack = clamped - (tracks[targetIdx]?.startOffset || 0)
-
-    console.log('[Player] seek', { absoluteTime, clamped, targetIdx, timeInTrack, currentIdx: currentTrackIdx.current })
-
-    if (targetIdx === currentTrackIdx.current) {
-      audio.currentTime = timeInTrack
-    } else {
-      currentTrackIdx.current = targetIdx
-      pendingSeek.current = timeInTrack
-      audio.src = trackUrl(tracks[targetIdx])
-      audio.load()
-      if (isPlaying) audio.play().catch((e) => console.warn('[Player] play() failed:', e))
-    }
-    seek(clamped)
-  }, [tracks, isPlaying, seek])
-
-  // Keyboard shortcuts — re-register when seekTo changes
   useEffect(() => {
     const handler = (e: KeyboardEvent) => {
       if (e.target instanceof HTMLInputElement) return
       if (e.code === 'Space') { e.preventDefault(); setPlaying(!isPlaying) }
-      else if (e.code === 'ArrowRight') seekTo(currentTime + 30)
-      else if (e.code === 'ArrowLeft') seekTo(Math.max(0, currentTime - 10))
+      else if (e.code === 'ArrowRight') seek(currentTime + 30)
+      else if (e.code === 'ArrowLeft') seek(Math.max(0, currentTime - 10))
     }
     window.addEventListener('keydown', handler)
     return () => window.removeEventListener('keydown', handler)
-  }, [seekTo, currentTime, isPlaying, setPlaying])
-
-  const onTimeUpdate = () => {
-    const audio = audioRef.current
-    if (!audio) return
-    const offset = tracks[currentTrackIdx.current]?.startOffset || 0
-    setCurrentTime(offset + audio.currentTime)
-  }
-
-  const onLoadedMetadata = () => {
-    const audio = audioRef.current
-    if (!audio) return
-    console.log('[Player] loadedmetadata', {
-      trackIdx: currentTrackIdx.current,
-      duration: audio.duration,
-      pendingSeek: pendingSeek.current,
-    })
-    if (pendingSeek.current !== null) {
-      try { audio.currentTime = pendingSeek.current } catch (e) { console.warn('seek failed', e) }
-      pendingSeek.current = null
-    }
-  }
-
-  const onCanPlay = () => {
-    if (pendingSeek.current !== null && audioRef.current) {
-      try { audioRef.current.currentTime = pendingSeek.current } catch {}
-      pendingSeek.current = null
-    }
-  }
-
-  const onEnded = () => {
-    const nextIdx = currentTrackIdx.current + 1
-    console.log('[Player] track ended', { nextIdx, total: tracks.length })
-    if (nextIdx < tracks.length) {
-      currentTrackIdx.current = nextIdx
-      pendingSeek.current = null
-      const audio = audioRef.current!
-      audio.src = trackUrl(tracks[nextIdx])
-      audio.load()
-      audio.play().catch((e) => console.warn('[Player] play() failed:', e))
-    } else {
-      setPlaying(false)
-      syncProgress()
-    }
-  }
-
-  const onError = () => {
-    const audio = audioRef.current
-    const err = audio?.error
-    const codeMap: Record<number, string> = {
-      1: 'MEDIA_ERR_ABORTED — Abruf abgebrochen',
-      2: 'MEDIA_ERR_NETWORK — Netzwerkfehler beim Laden',
-      3: 'MEDIA_ERR_DECODE — Format nicht dekodierbar',
-      4: 'MEDIA_ERR_SRC_NOT_SUPPORTED — Quelle nicht unterstützt (404/Format/MIME)',
-    }
-    const msg = err ? `${codeMap[err.code] || `Code ${err.code}`}${err.message ? ': ' + err.message : ''}` : 'Unbekannter Fehler'
-    console.error('[Player] audio error', {
-      code: err?.code,
-      message: err?.message,
-      src: audio?.src,
-      networkState: audio?.networkState,
-      readyState: audio?.readyState,
-    })
-    setPlayerError(msg)
-  }
+  }, [currentTime, isPlaying, seek, setPlaying])
 
   const fmtTime = (s: number) => {
     if (!isFinite(s)) return '0:00'
@@ -231,7 +66,6 @@ export default function AudioPlayer() {
   const meta = item?.media?.metadata || {}
   const title = meta.title || item?.relPath || ''
   const author = meta.authors?.[0]?.name || ''
-
   const currentChapter = [...chapters].reverse().find((c: any) => currentTime >= c.start) || chapters[0]
 
   const addBookmark = async () => {
@@ -247,17 +81,13 @@ export default function AudioPlayer() {
     pct: duration > 0 ? (c.start / duration) * 100 : 0,
   }))
 
+  const streamUrl = session?.audioTracks?.[0]?.contentUrl
+  const trackInfo = session?.audioTracks
+    ? `${session.audioTracks.length} Track(s), Gesamt-Dauer ${fmtTime(duration)}`
+    : 'Keine Tracks'
+
   return (
     <div className="flex flex-col h-full bg-background p-6 overflow-y-auto">
-      <audio
-        ref={audioRef}
-        onTimeUpdate={onTimeUpdate}
-        onLoadedMetadata={onLoadedMetadata}
-        onCanPlay={onCanPlay}
-        onEnded={onEnded}
-        onError={onError}
-      />
-
       <div className="flex items-center justify-between mb-6">
         <button onClick={() => setExpanded(false)} className="text-muted hover:text-ink transition-colors">
           <ChevronLeft size={24} />
@@ -288,9 +118,12 @@ export default function AudioPlayer() {
         <div className="mb-4 px-4 py-3 rounded-lg border border-red-500/40 bg-red-500/10 text-red-300" style={{ fontSize: '12px' }}>
           <p className="font-medium mb-1">Audio-Fehler</p>
           <p className="opacity-80">{playerError}</p>
-          <p className="opacity-60 mt-2" style={{ fontSize: '10px' }}>
-            Stream-URL: <span className="font-mono break-all">{tracks[currentTrackIdx.current]?.contentUrl}</span>
-          </p>
+          {streamUrl && (
+            <p className="opacity-60 mt-2" style={{ fontSize: '10px' }}>
+              Stream-URL: <span className="font-mono break-all">{streamUrl}</span>
+            </p>
+          )}
+          <p className="opacity-60 mt-1" style={{ fontSize: '10px' }}>{trackInfo}</p>
         </div>
       )}
 
@@ -305,7 +138,7 @@ export default function AudioPlayer() {
           />
           <input
             type="range" min={0} max={duration || 0} step={1} value={currentTime}
-            onChange={(e) => seekTo(parseFloat(e.target.value))}
+            onChange={(e) => seek(parseFloat(e.target.value))}
             className="absolute inset-0 w-full opacity-0 cursor-pointer h-full"
           />
         </div>
@@ -316,7 +149,7 @@ export default function AudioPlayer() {
       </div>
 
       <div className="flex items-center justify-center gap-6 mb-6">
-        <button className="text-muted hover:text-ink transition-colors" onClick={() => seekTo(currentTime - 30)}>
+        <button className="text-muted hover:text-ink transition-colors" onClick={() => seek(Math.max(0, currentTime - 30))}>
           <SkipBack size={28} />
         </button>
         <button
@@ -328,7 +161,7 @@ export default function AudioPlayer() {
         >
           {isPlaying ? <Pause size={22} fill="currentColor" /> : <Play size={22} fill="currentColor" />}
         </button>
-        <button className="text-muted hover:text-ink transition-colors" onClick={() => seekTo(currentTime + 30)}>
+        <button className="text-muted hover:text-ink transition-colors" onClick={() => seek(currentTime + 30)}>
           <SkipForward size={28} />
         </button>
       </div>
@@ -393,7 +226,7 @@ export default function AudioPlayer() {
           <List size={20} />
         </button>
 
-        <button className="text-muted hover:text-ink transition-colors" onClick={() => setMuted(!muted)}>
+        <button className="text-muted hover:text-ink transition-colors" onClick={() => { setLastVolume(volume || 1); setMuted(!muted) }}>
           {muted ? <VolumeX size={20} /> : <Volume2 size={20} />}
         </button>
       </div>
@@ -402,7 +235,7 @@ export default function AudioPlayer() {
         <ChapterList
           chapters={chapters}
           currentTime={currentTime}
-          onSeek={seekTo}
+          onSeek={seek}
         />
       )}
     </div>
diff --git a/frontend/src/components/player/MiniPlayer.tsx b/frontend/src/components/player/MiniPlayer.tsx
index 830af60..1948df2 100644
--- a/frontend/src/components/player/MiniPlayer.tsx
+++ b/frontend/src/components/player/MiniPlayer.tsx
@@ -5,7 +5,7 @@ import CoverImage from '../common/CoverImage'
 import { coverUrl } from '../../api/items'
 
 export default function MiniPlayer() {
-  const { item, currentTime, duration, isPlaying, setPlaying, stop, setExpanded } = usePlayerStore()
+  const { item, currentTime, duration, isPlaying, setPlaying, stop, setExpanded, playerError } = usePlayerStore()
   if (!item) return null
 
   const meta = item.media?.metadata || {}
@@ -15,11 +15,11 @@ export default function MiniPlayer() {
 
   return (
     <div className="h-full flex flex-col bg-surface border-t border-divider">
-      {/* Progress track */}
+      {/* Progress track (oder Fehler-Strich rot) */}
       <div className="bg-muted2 relative" style={{ height: '4px', borderRadius: '2px' }}>
         <div
-          className="h-full bg-ink"
-          style={{ width: `${pct}%`, borderRadius: '2px', transition: 'width 0.5s linear' }}
+          className={`h-full ${playerError ? 'bg-red-500' : 'bg-ink'}`}
+          style={{ width: playerError ? '100%' : `${pct}%`, borderRadius: '2px', transition: 'width 0.5s linear' }}
         />
       </div>
 
diff --git a/frontend/src/store/playerStore.ts b/frontend/src/store/playerStore.ts
index 68b6979..a0c1a1d 100644
--- a/frontend/src/store/playerStore.ts
+++ b/frontend/src/store/playerStore.ts
@@ -12,10 +12,12 @@ interface PlayerState {
   isPlaying: boolean
   playbackRate: number
   volume: number
-  sleepTimer: number | null       // Sekunden verbleibend
+  sleepTimer: number | null
   sleepTimerActive: boolean
   chapters: Chapter[]
   expanded: boolean
+  seekRequest: { time: number; counter: number } | null
+  playerError: string | null
 
   play: (item: any) => Promise<void>
   stop: () => Promise<void>
@@ -28,6 +30,7 @@ interface PlayerState {
   setSleepTimer: (seconds: number) => void
   cancelSleepTimer: () => void
   setExpanded: (v: boolean) => void
+  setPlayerError: (msg: string | null) => void
   syncProgress: () => Promise<void>
 }
 
@@ -46,6 +49,8 @@ export const usePlayerStore = create<PlayerState>((set, get) => ({
   sleepTimerActive: false,
   chapters: [],
   expanded: false,
+  seekRequest: null,
+  playerError: null,
 
   play: async (item: any) => {
     const { session: oldSession, stop } = get()
@@ -60,9 +65,10 @@ export const usePlayerStore = create<PlayerState>((set, get) => ({
       chapters: session.chapters || [],
       isPlaying: true,
       expanded: false,
+      seekRequest: null,
+      playerError: null,
     })
 
-    // Sync alle 15 Sekunden
     if (syncInterval) clearInterval(syncInterval)
     syncInterval = setInterval(() => get().syncProgress(), 15000)
   },
@@ -74,10 +80,13 @@ export const usePlayerStore = create<PlayerState>((set, get) => ({
     if (session) {
       try { await closeSession(session.id) } catch { }
     }
-    set({ item: null, session: null, isPlaying: false, currentTime: 0, sleepTimerActive: false })
+    set({ item: null, session: null, isPlaying: false, currentTime: 0, sleepTimerActive: false, seekRequest: null, playerError: null })
   },
 
-  seek: (time) => set({ currentTime: time }),
+  seek: (time) => set((s) => ({
+    currentTime: time,
+    seekRequest: { time, counter: (s.seekRequest?.counter || 0) + 1 },
+  })),
 
   setPlaying: (v) => set({ isPlaying: v }),
 
@@ -110,6 +119,8 @@ export const usePlayerStore = create<PlayerState>((set, get) => ({
 
   setExpanded: (v) => set({ expanded: v }),
 
+  setPlayerError: (msg) => set({ playerError: msg }),
+
   syncProgress: async () => {
     const { session, currentTime, duration, item } = get()
     if (!session || !item) return