Request: Kernel Quirk for Elektron USB boxes

Patchbox OS
1

Ive been routing my gear successfully with Patchbox for audio and MIDI but recently when trying to get my Zoom L-8 to use the Elektron AH MK2 as a send I kept getting bitcrushed audio on the USB return.

I found a thread on another forum that solves it with quirks and it appears to affect many devices. So is it possible to get this added to the kernel? Im happy to test if so.

https://www.elektronauts.com/t/solved-class-compliant-mode/198727/21

In Patchbox I tried adding these lines to /etc/modprobe.d/alsa-base.conf to simulate one users success:

#1 Didnt work USB panic on unrecognized argument:
options snd-usb-audio quirk_flags=0x19351052:0x00000008

#2 Try bypass standard class-compliant polling and initialize the interface using standard asynchronous implicit audio streaming feedback endpoints
options snd-usb-audio index=3 vid=0x1935 pid=0x1052 device_setup=1

Attempt #2 saw the device but still had missing frames when I ran journalctl --user -u pipewire -f

Aug 15 15:42:20 patchbox pipewire[1016]: spa.alsa: front:3: follower delay:1137 target:768 thr:512, resync (63 missed)

2

I was able to get this working using the alsa.conf after all and learned a lot, I didnt really understand how quirks were implemented. I used a Scarlett 2i2 3rd Gen device type, and setting the zoom l8s custom linux driver parameter. Now I can send my Zoom inputs to the Heat and Return via the USB tracks :slight_smile:

# 1. Force Heat to use completely independent interface buffer profile
options snd-usb-audio implicit_fb=1 quirk_alias=19351052:12358210

# 2. Prevent Zoom driver from probe/bind secondary class compliant endpoints
options snd-usb-zoom fast_boot=1