alsa-project/alsa-lib issue #178 was opened from lentferj: I installed 5.14 kernel from this source (https://github.com/geoffreybennett/scarlett-gen2/releases) on Debian Buster to test out the better USB audio latency. I found that both Bitwig and Ardour6 cannot start anymore when using ALSA MIDI raw devices. In Bitwig the sound engine keeps crashing and Ardour6 doesn't start at all when choosing raw devices. In Ardour6 I see this: ``` ALSA lib rawmidi_hw.c:100:(snd_rawmidi_hw_params) SNDRV_RAWMIDI_IOCTL_PARAMS failed: Invalid argument ardour-6.9.0: rawmidi.c:268: snd_rawmidi_open_conf: Assertion `err >= 0' failed. Aborted ``` I also tried to access devices directly with amidi, same result. ``` $ amidi --dump -p hw:5 ALSA lib rawmidi_hw.c:100:(snd_rawmidi_hw_params) SNDRV_RAWMIDI_IOCTL_PARAMS failed: Invalid argument amidi: rawmidi.c:268: snd_rawmidi_open_conf: Assertion `err >= 0' failed. Aborted ``` I manually upgraded alsa-lib and alsa-utils to 1.2.5, but I still have the same problem: ``` $ which amidi /usr/bin/amidi lentferj@ts-d20:~$ ls -l /usr/bin/amidi -rwxr-xr-x 1 root root 57064 Sep 19 18:34 /usr/bin/amidi lentferj@ts-d20:~$ ldd /usr/bin/amidi linux-vdso.so.1 (0x00007ffc50c9b000) libasound.so.2 => /usr/lib/libasound.so.2 (0x00007f9c97c85000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f9c97b02000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f9c97afd000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f9c97adc000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f9c9791b000) librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f9c97911000) /lib64/ld-linux-x86-64.so.2 (0x00007f9c97dc0000) lentferj@ts-d20:~$ ls -l /usr/lib/libasound.so.2 lrwxrwxrwx 1 root root 18 Sep 19 18:29 /usr/lib/libasound.so.2 -> libasound.so.2.0.0 lentferj@ts-d20:~$ ls -l /usr/lib/libasound.so.2.0.0 -rwxr-xr-x 1 root root 5242136 Sep 19 18:29 /usr/lib/libasound.so.2.0.0 lentferj@ts-d20:~$ uname -a Linux ts-d20 5.14.0 0000021 SMP Mon Aug 30 00:46:47 UTC 2021 x86_64 GNU/Linux lentferj@ts-d20:~$ amidi -l Dir Device Name IO hw:2,0,0 Saffire 6USB2.0 MIDI 1 IO hw:3,0,0 Neutron(1) MIDI 1 IO hw:4,0,0 Pulse2 MIDI 1 IO hw:5,0,0 LPK25 MIDI 1 lentferj@ts-d20:~$ amidi --dump -p hw:5 ALSA lib rawmidi_hw.c:100:(snd_rawmidi_hw_params) SNDRV_RAWMIDI_IOCTL_PARAMS failed: Invalid argument amidi: rawmidi.c:256: snd_rawmidi_open_conf: Assertion `err >= 0' failed. Abgebrochen ``` When booting back to a 5.10 kernel the problems disappear. I also reported this on the Ardour Tracker ( https://tracker.ardour.org/view.php?id=8800 ). Issue URL : https://github.com/alsa-project/alsa-lib/issues/178 Repository URL: https://github.com/alsa-project/alsa-lib