Motu M2 USB Interface on Linux

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knillenhower
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Joined: Sun Jan 19, 2020 10:08 pm

Re: Motu M2 USB Interface on Linux

Post by knillenhower »

very helpful link! clearly explains the issue. somehow my search engines missed that.

habys
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Re: Motu M2 USB Interface on Linux

Post by habys »

puleglot wrote:
Tue Apr 07, 2020 10:18 pm
knillenhower wrote:
Tue Apr 07, 2020 9:53 pm
any help with the duplex profile issue would be greatly appreciated.
I can only suggest you to follow the bug report below:
https://bugzilla.kernel.org/show_bug.cgi?id=207023
Is anyone else running using this? I've got 5.6.12 patched with it and it does indeed work, but the card still seems flaky, and I need to restart my machine occasionally because the audio gets stuck. I would post on the bug but I don't really have anything useful to say yet. Anyone else tried?

knillenhower
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Re: Motu M2 USB Interface on Linux

Post by knillenhower »

hi habys,
no haven't tried the patch yet. but it will be included in the next kernel 5.8 (mainline right now). if you use pulseaudio have you tried putting this

Code: Select all

default-sample-rate = 48000
avoid-resampling = no
into /etc/pulse/daemon.conf?

knillenhower
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Re: Motu M2 USB Interface on Linux

Post by knillenhower »

also tried the duplex patch now on kernel 5.8-rc2 and 5.7.6. the patch was first submitted to kernel 5.8 and later applied to 5.7.6 and 5.4.49 (2020-06-24). the duplex option is now back in the pulseaudio settings however there is still an unfortunate bug i can confirm: when playing playback and then starting a recording stream and stopping it, the playback will stop. only restarting the playback software will bring back the audio output. alsa developers discuss the issue on the kernel bugzilla and the alsa developers mailinglist but i think there is no solution yet:

https://bugzilla.kernel.org/show_bug.cgi?id=207023

https://mailman.alsa-project.org/piperm ... 68524.html

i also noticed a complete system freeze twice when logging in to the desktop environment (xorg + lightdm + cinnamon) but i did not investigate any further so far, might not be related to the audio device.

fanantoxa
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Re: Motu M2 USB Interface on Linux

Post by fanantoxa »

Hey! I've got Motu M2 recently and trying to make it work.
Flowed some steps from this post
and
https://panther.kapsi.fi/posts/2020-02-02_motu_m4

I did have it work with JACK but it worked out until is disconnect/connect again.
(but it won't work for me anyway since I'm switching from pc<->laptop few times a day and I have other sound devices, so I wish it will work with puseaudio)

One notice that if I use PulseAudio and select for output to M2 and play Youtube in browser (chrome), after I switch to input to Motu youtube starts to hang
It shows loading circle but it can't load video, the same happen if I open another tab.
Fixed only when I switch input to another device and restart chrome.

I've added comments about this to this bugzila ticket, but no response so far.
https://bugzilla.kernel.org/show_bug.cgi?id=207023

I can also try to help debug/check it (but I'll need some help with it)

If there anything I can help with please let me know

puleglot
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Re: Motu M2 USB Interface on Linux

Post by puleglot »

fanantoxa wrote:
Tue Jul 14, 2020 6:09 pm
One notice that if I use PulseAudio and select for output to M2 and play Youtube in browser (chrome), after I switch to input to Motu youtube starts to hang
It shows loading circle but it can't load video, the same happen if I open another tab.
Fixed only when I switch input to another device and restart chrome.
Are you sure jack is not running and not monopolizing the card?

fanantoxa
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Re: Motu M2 USB Interface on Linux

Post by fanantoxa »

That happen when jack is not even installed.
Or if everything go from/to Jack but I turned device off and on.

So that might be 2 issues:
- only pulsaudio doesn't work in duplex mode
- only jack when device reconnected while system running

And they both lead to same issue that applications that where using Motu as output getting stuck somehow.

Any logs I can check for issues?

knillenhower
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Re: Motu M2 USB Interface on Linux

Post by knillenhower »

@fanantoxa: if have the exact same issue with firefox/youtube and the M2. without any jack. i can get youtube to work again only by stopping the input stream and restarting the browser. duplex is just not working correctly yet with pulseaudio. only putting the interface either in input mode or output mode (pavucontrol) should resolve the issue. but then no duplex is possible of course.

fanantoxa
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Re: Motu M2 USB Interface on Linux

Post by fanantoxa »

After some time and investigation.

Patch created here:
https://bugzilla.kernel.org/show_bug.cgi?id=207023

Already in the kernel:
I have Ubuntu Kernel 5.7.11-050711-generic

Also I've Updated pulseaudio to last 13.0 version,

Now I have some hanging issues in some corner cases.
But currently I can use Motu M2 for both output and input at the same time!!

(for mo details read my comments in post)

fanantoxa
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Re: Motu M2 USB Interface on Linux

Post by fanantoxa »

After some time trying to make it work.
With last kernel I could get and using JACK to work with MOTU M2 and wire it up to pulseaudio works.

Kinda. :(
If I disconnect/connect MOTU or turn OFF/ON. It hangs everything (like youtube) as it did before.
More on that JACK get crashed. And note responsive (until I reboot whole laptop)

For now tt unusable even just for hangout/zoom/etc. Probably for music recording too. (at least for me)

Not sure what to do. Will try later so make some more changes to make it work.

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bluebell
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Location: Saarland & Frankfurt, Germany

Re: Motu M2 USB Interface on Linux

Post by bluebell »

Disconnecting an USB audio interface or switching it off while jackd is running is always a problem and should be avoided.
Linux – MOTU UltraLite AVB – Qtractor – https://soundcloud.com/suedwestlicht

fanantoxa
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Re: Motu M2 USB Interface on Linux

Post by fanantoxa »

> Disconnecting an USB audio interface or switching it off while jackd is running is always a problem and should be avoided.

Sad to hear. Sounds like a major bug. There are many cases why USB device can be disconnected.

But I cleaned all settings and removed JACK.
And It partly work now with pulseaudio.


But still when I turn off and on device it hangs.
I managed to get off this hang state without restarting chrome:
- changed input to another device (WebCam in my case)
- turn off and on motu again
- got to output setting and click to internal speakers and back for a few times.

After that I'm have working only output and if I try to use input at the same time it hangs as usual.

So i kinda partly working. BUt mostly not usable in my case :(
(I have a USB switch between laptop and PC and switch between few time during the day)

foul_owl
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Re: Motu M2 USB Interface on Linux

Post by foul_owl »

For what it's worth, I've managed to get my MOTU M4 working on a default Debian 10 install by doing the following:

* Connect M4 to powered USB hub (NOT to computer! Power only!)
* Wait for M4 to boot
* Confirm hardware monitoring works with test input
* Connect M4 to computer
* Short delay (15 seconds or so)
* M4 now works, I can record on all four channels AND play back audio on all 4 channels at once with no issues. (Using Reaper for my DAW, ALSA as the audio system)

But....my latency jumps all over the place, I'm guessing probably because of the USB hub. (nothing else is connected to the hub but still)

If I connect the M4 directly to the computer, it freezes. No audio, not even from hardware monitoring. This is because of pulseaudio trying to interact with it too early?

AngelMixu
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Joined: Tue Oct 27, 2020 9:15 pm

Re: Motu M2 USB Interface on Linux

Post by AngelMixu »

Hi people!

I've got a MOTU M4 and this freezes are also happening to me :/

I've tryied using plain ALSA, Jack, PulseAudio, and also PipeWire... and in all cases it happens the same: sometimes when I boot the machine, it doesn't produce any sound nor the UV levels move; and if there no audio playing for some time, it goes into that freeze state again.

I'm using Arch Linux on latest builds/packages, and it's still happening :(

If you have any suggestion, please post it around!
Thanks!

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