🔴 SmartDJCache concurrent Dictionary crash (April 27+28 crash logs):
- EXC_BAD_ACCESS + doesNotRecognizeSelector in bulkImport()
- memoryCache dictionary mutated from main thread (loadBulkCache)
and background Task.detached (bulkImport) simultaneously
- Fix: NSLock serializes all memoryCache reads and writes
🔴 stopAVPlayer removeTimeObserver crash (April 30 crash log):
- SIGABRT in -[AVPlayer removeTimeObserver:] from Previous button
- timeObserver registered on old player, self.player swapped to
crossfade's active player by finalizeCrossfade
- Fix: remove observer from OLD player at both swap sites before
assignment + reorder stopAVPlayer (observer before replaceCurrentItem)
🟡 Audit fixes (no crash logs, preventative):
- KVO in radioSeekBack wrapped in DispatchQueue.main.async
- Stale vis Task guarded by songId in all MainActor.run blocks
- CHANGELOG.md with full findings documentation
Features:
- Dual-AVPlayer Smart DJ crossfade with LUFS normalization
- Mitsuha-style FFT visualizer (real-time + offline pre-computed)
- Companion API integration (Smart DJ, tag editing, vis frames)
- Offline-first SyncEngine with delta sync and album detail pre-caching
- Audio pre-fetcher for gapless queue playback
- Optimistic action queue (star/unstar with background retry)
- ShazamKit recognition with MusicKit preview playback
- Radio streaming with HLS/PLS/M3U support and buffer seek
- Watch app with Crown Sequencer and Ultra speaker support
- Batch metadata editing with album_artist fix for split albums
- Cache-first UI pattern across all views
- NWPathMonitor offline detection with reactive song greying
