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MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 9:26 am
by dailybug2
An input track if set to stereo and connected to the jack input (stereo too) only receives signal on the left channel, according to the level meters. A stereo recording from this input shows signal on the left channel only.

Swapping the jack input ports (system:capture_1, system:capture_2) for the input track does not result in signal on the right channel. Whatever I do, only the left channel shows signal.

I tested this on the same jackd instance running with audacity (audio mode: jack, stereo track) and it works fine, out of the box. So my audio interface and the jack configuration are OK.

I uninstalled pulseaudio (nothing good for anyway).
I re-installed MusE + ALSA utils + jackd + jackd utils
I removed all the configuration files in my home directory.
I'm not using a specific ALSA setup - anything at default config.

All components are recent, updated and/or rebuilt this week.

Result: Audio recording broken for MusE 3.1.0 built from GIT @ Xubuntu-20.04.
I wonder if anybody else has experienced this.

Please tell me if there are any specific logs I should provide.
Should I file a bug report on github (no account yet)?

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 11:40 am
by dailybug2
Here you can see how the inputs are connected; I guess this should be OK:
Image

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 1:47 pm
by oscillator
Hmmm....I have only ever done mono recording.

So 1st try with built in audio.

Seems like a mismatch between what MusE thinks and what QJackCtl shows. And only audio on left channel. On the other hand the internal audio is a mic, so next I will try an external stereo sound card.
muse_sterero_builtin.jpg

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 2:06 pm
by oscillator
2nd try, USB audio card, radio fed into ch 1+2.

Only audio on left channel. The Advanced routing display shows System capture 2 going into Input 1, but QJackCtl doesn't show this. Strangely, for a couple of seconds I could see both Input 1 - 0 AND Input 1 - 1 for MusE in QJackCtl, but it disappeared.

I can't get it to work, too.
muse_sterero_card.jpg

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 2:16 pm
by oscillator
One possibe solution is having TWO input tracks (for L and R) feeding into the same Wave track. Works for me:

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 5:37 pm
by dailybug2
Thanks for your effort. This is a major issue, a DAW which is not able to record stereo tracks?! Huh?! I created a ticket on github.com. Of course I know that MusE is a voluntary open source software and a fix may take some time, if any. I'll stay tuned.

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 7:57 pm
by oscillator
dailybug2 wrote:
Thu May 21, 2020 5:37 pm
Thanks for your effort. This is a major issue, a DAW which is not able to record stereo tracks?! Huh?! I created a ticket on github.com. Of course I know that MusE is a voluntary open source software and a fix may take some time, if any. I'll stay tuned.
Maybe we are doing something wrong. Let's wait for any of the devs to comment.

Did you try my solution with two input tracks?

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 9:07 pm
by Tim E. Real
Thanks for the detailed reports!
Sure looks like something not right here. Will check ASAP...

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Thu May 21, 2020 10:19 pm
by Tim E. Real
Verified here.
Same results as what you show.

OK Now I'm pissed. Two things broken in one week that were working ;-)
I swear that audio input was working. I play my keyboard through it all the time.
And it goes all the way back to the official 3.1 release you say? ie. You're not using git? Hm...

These types of issues I consider top-tier extremely important.
Don't hesitate to report them. Thanks. Hang in there... Might be a long-ish tense session. Checking...

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Sun May 24, 2020 5:48 am
by Tim E. Real
I broke it one month ago. Fixed in git master now. Thanks!

- Fix regression at 06.04.2020: Can't connect Jack ports to audio input/output tracks R chan.
Don't check out of bounds index in AudioInput/Output::registerPorts(). When it is called
by Audio::msgSetChannels(), the new number of channels has not been set yet.

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Sun May 24, 2020 9:01 am
by oscillator
Tim E. Real wrote:
Sun May 24, 2020 5:48 am
I broke it one month ago. Fixed in git master now. Thanks!
Great! Have only tested with a mono mic conncted to both L and R but it works and records on both channels! Thank you very much @Tim E. Real !

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Sun May 24, 2020 9:40 am
by dailybug2
Rebuilt from scratch and tested recording some eeeextra wide stereo pad, switching back and forth between stereo and mono, saving and loading the project - I'm suspicious! Works now.
Thanks for this incredible quick fix, even if it just commented out two statements in the code ;-)

Re: MusE records left audio channel only on Xubuntu-20.04

Posted: Sun May 24, 2020 4:06 pm
by Tim E. Real
Two lines and another million brain cells gone ;-)
Thanks for your help catching this. Sometimes these blunders happen.
Be suspicious... be very suspicious...