Four findings from a day's cbd.log and a 121-entry queue.
**Dedup by title.** The provider-item identity removed nothing from that
queue — 121 entries, 121 distinct ids — while three "Sink Into The Hips"
sat in it: two remixes and the album version, 171/189/228s. Those are
different recordings and merging them by default would silently discard a
version the user chose, so the default stands and `DedupQueue` gains a
`by_title` flag: lowercased (artist, title), survivor = the playing entry
else the *longest* take. Own key everywhere (`U`, `queue dedup --titles`)
because it throws recordings away. Duration-tolerant matching was the
third option and is not worth it: every same-title group in that queue
differed by tens of seconds, so a safe tolerance caught nothing.
**stderr no longer points at the terminal.** tracing goes to a file
because the TUI owns the screen, but fd 2 did not — and in the bundled
`cbd` the ALSA C library shares the process, so its "underrun occurred"
printed straight onto the interface, scrolled the terminal a line and
left the layout looking shifted (the queue appearing to bleed into the
now-playing pane; ratatui repaints only changed cells, so it persisted).
The message was lost too. One dup2 before the alternate screen sends fd 2
to `<log dir>/cbd.stderr.log`, so those diagnostics are kept instead.
**The spectrum flapped ~1/s during playback**, 3664 times in one log.
tokio's default MissedTickBehavior::Burst keeps the absolute schedule, so
once the per-tick FFT lateness reaches a whole period two ticks fire back
to back and the second necessarily sees no new frames — read as silence,
which zeroed the bars. Now `Delay`, plus a FlowDetector that wants two
consecutive empty ticks before declaring idle.
**The one ERROR in the log was a shutdown race**, mislabelled: "request
to server failed: sending on a closed channel" was the orchestrator's
send to the UI channel after the UI thread exited. It now reports the UI
closing at info and stops the loop instead of spinning on a stream nobody
reads.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
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