Sound demos playing white noise at end of sample before looping

[petemoore]

Hi Peter,

This is an unbelievably valuable repository, first of all, I am extremely indebted to you for all of the hard work you have done putting it together.

I've been working on rpi 3 port of PiFox and I'm having problems with the sound. I discovered your sound demos, and decided to try one out to see if it played correctly for me on my rpi 3b.

I tested the Sound/PWM/12Bit/44100Hz/Stereo/CPU demo, and it played the sample perfectly, until it hit the end of the sample, after which several seconds of white noise are played, before the sample restarts. The white noise is very similar to the white noise I am experiencing in my PiFox port, so I suspect it is a similar issue. My thoughts are maybe this could be due to a firmware update, or possibly my rpi 3b has slightly different clock timings to the rpi 3 base model, or perhaps there is something else at play.

Do you happen to know if this demo should work with the latest firmware on a rpi 3, or is there any debug information I can get you that might hint at the cause of the white noise?

I'm happy to dump some system register values to UART etc if that helps with a diagnosis. Also if you'd like me to try out any of the other samples, or try explicitly the kernel7.img vs kernel8.img versions, I can do that. I can also make a recording, if that helps. :-)

Once again, many thanks for this amazing repository!

Kind regards,
Pete

[petemoore]

Could this be related to #10?