I've also not had great luck with MOTU devices (624, 8pre-es). Granted AFAIK, they're still not supported in mainline kernel, but I found a few kernel modules on github. Those kernel modules work in that the audio interfaces are detected and I can play audio, but after a couple mins (sometimes immediately), it sounds like I'm getting buffer under runs even if I max out my buffers. If I disconnect and reconnect the devices it will sometimes work for another few mins. They work perfectly on windows. My preferred DAW is also windows only, but I can run a windows VM and do USB pass through on the either of the audio interfaces (other is connected via AVB), and it works great. So this is how I do audio, but this also means I'm using onboard audio for everything except the windows VM.