Bug: occasional audio output glitch on v1.0.8

[mpogue2]

I've only heard this twice, but it really should not ever occur. Very short audio output pop. Does not stop playback, just annoying. I use SquareDesk every time I call, and I never head this on a previous version, so it could be related to the update to later version of Qt. I think there was one change related to looping, but that should not have the ability to cause this audible problem.

M1 MacBook Air, Sonoma. Activity monitor showed no spikes in CPU usage, that I am aware of.

[mpogue2]

This could also be a consequence of recent updates to MacOS itself.

[mpogue2]

I now have a longevity test for audio playback.

• plays a 1KHz tone (28 seconds on, 2 seconds off) for 1 hour
• recorded by a separate process (Audio Hijack) to lossless MP4 format
• converted to WAV format (ffmpeg -I infile.mp4 outfile.wav)
• scan (custom R script) the audio for zero crossings
• glitch would be detected as any missing zero crossings, or unexpected spacing between zero crossings (this method will detect missing, delayed, or repeated audio in both tone and silence sections (although problems in a silence section can be detected, could not dive deeper on those. But, we can go to the sample level if an error occurs within a tone segment.)

V1.0.8 RESULTS: I ran this test for 1 hour on top-of-tree (while I was working on other stuff, so the rest of the system was NOT quiescent), and zero glitches were detected -- output was essentially perfect for that hour, near as I can determine.

[mpogue2]

From #1134, copying these results here:

After 2 full hours of glitch testing:

• Qt6.7.1 = 1 hour, 0 glitches
• Qt6.7.2 = 1 hour, 0 glitches
• TOTAL = 2 hours, 0 glitches, 90% confidence interval = [0.0, 1.5] glitches per hour

Note that I am running plugged into a power supply. It's possible that running off battery alone would give different results. I'll have to try that sometime...

[mpogue2]

Tested 1 hour with Qt6.7.2, v1.0.9, and 0 glitches, running on battery power alone. Total: 3 hours, 0 glitches, 90%CI = [0.0, 1.0] glitches per hour

I'm declaring this one fixed for now. Will reopen if glitches occur again in the future.