Apparently this was a well reported problem for RPI4 Buster in 2019. Is this a regression for Patchbox OS or has it been fixed?
I have a NI Rig Kontrol 3 supported by ALSA kernel driver, snd-usb-caiaq. I am trying to use this on my RPi4 using Patchbox OS on the mainline kernel. Every time I plug my Rig Kontrol into the USB, the whole OS slows to a jerky crawl. The shell or Desktop either one gets updated every other second. Its unusable. It goes back to normal when unplugging the unit. This thread from the RPI forum describes the problem completely.
I just verified that problem is exclusive to the RPi4. Without changing the config, I replaced the card in my old RPi3, and the audio system works as expected. My Kontrol Rig was able to output audio from Speaker-Test.
As a result, I am moving my development to RPi3. This is unfortunate as that was not the platform I was targeting, but it will suffice for now. Hopefully, this will get sorted out as it appears that snd-usb-caiaq based NI external audio hardware is dead on RPi4…
Hey, this looks like a kernel issue, you may try checking if you’re using the latest stock kernel (select the stock kernel in patchbox → kernel menu, reboot, run sudo apt update && sudo apt upgrade afterwards, if it updated raspberrypi-kernel package, reboot again).
If the issue occurs on latest stock kernel, raise an issue for Raspberry Pi foundation here: Issues · raspberrypi/linux · GitHub