Intermittent audio distortion w/ Patchbox, MODEP

Hi, all. I picked up a Raspberry Pi 5 to try out Patchbox OS and, eventually, a PiSound. Unfortunately, running Patchbox and MODEP, I experience problems with intermittent audio distortion.

The distortion sounds very digital — not crackling, but more like bad buffering? — and it comes and goes. There’s no specific trigger or pattern I’ve been able to identify.

To troubleshoot, I’ve followed documentation here carefully, experimented based on online research, tweaked kernels and settings, reflashed and reset to start over, etc. Unfortunately, I have not been able to resolve this issue.

I think I read an old post here that described a similar problem. The response, if I remember correctly, was that it sounded like a power-delivery issue. If that’s the case, a different power supply might solve the issue, right? It didn’t. If that’s the case, shouldn’t it be an issue with any other OS? It’s not.

For comparison’s sake, I switched to Zynthian OS — using exactly the same Pi, official power supply, USB soundcard, etc. I have not experienced anything like what I described above with that OS or their port of MOD UI.

To be clear, I’m not here to complain. I’m just looking for advice AND I’d love to help resolve this, especially if it might be something that can be solved at the OS or module level. Please let me know if you have any ideas, if there are any diagnostics or settings or config files I can check or share, etc.

FWIW, I have not installed the active cooler or real-time battery on the Pi, but I plan to do so later today and will test a fresh, updated Patchbox install after.

THANKS MUCH!

If using Raspberry Pi 5, you should install a cooler - if it gets too hot, it will slow itself down. Pi 4 and earlier are ok without any coolers.

Also, try using higher audio buffer settings in the Jack configuration (through the patchbox utility)

I was experiencing the same issue which was driving me insane bc it seemingly only occurred when I had the OJD drive pedal engaged. Intermittent popping sounds almost like cellphone or WiFi interference would just appear randomly. Turns out, since I was only using TS cable on the input side, I only thought to connect the left input channel on the pedalboard… I mean that seemed like the logical thing to do. As I turns out, it wasn’t until I connected the right input channel to the right output on the pedal that the weird intermittent popping sound disappeared.

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