Ever since I originally installed my RigPi it has had an annoying audio pop, sometimes accompanied by garbled audio before the pop. This happens every few minutes. Using a higher quality microSD helped, but never removed the problem. Problem only happens when RSS software is running with a user logged in.
I have finally found that the source of this is a lot of IO to /home/pi/.cache/lxsession/LXDE-pi/run.log. Going back to my original microSD that came with the RigPi, the problem exists from day one. (When the RSS software started up with this constant logging, the microSD was periodically getting IO bound, slowing IO, and causing the "pop". This is not an RSS software problem, but adding its IO load brings the problem out.)
The workaround is to redirect this error/warning log file to /dev/null to stop writing constantly to the microSD. If you have need to see that logging, you have to remove the redirection.
The root of the problem seems to be that, after the following is logged to run.log:
ALSAAudioOutput: Initialized 1 channel, 48000 hz mixer
Warning: The VAD has been replaced by a hack pending a complete rewrite
There is constant logging of huge numbers of the following:
warning: Unknown speex_preprocess_ctl request: 2
warning: Unknown speex_preprocess_ctl request: 46
warning: Unknown speex_preprocess_ctl request: 30
..... continues constantly like this.
- Do others see that the /home/pi/.cache/lxsession/LXDE-pi/run.log file keeps getting written to and growing on your RigPi?
- What is the "Unknown speex_preprocess_ctl" error about? The best fix would be to find why the warning is being written. With this warning, I see no audio or functionality problems (except for the excessive error logging).
By the way, using an FT-991 connected to RigPi using just the USB cable. Also, I see this problem in both "stretch" and when I use a microSD that has been upgraded to "buster".