After upgrading to trusty, ALSA midi connection (aconnect) doesn't seem to work right

Posted by SougonNaTakumi on Ask Ubuntu See other posts from Ask Ubuntu or by SougonNaTakumi
Published on 2014-06-07T08:40:31Z Indexed on 2014/06/07 9:36 UTC
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Previously in kubuntu 13.10 I was able to open vmpk or plug in a midi keyboard, and provided that TiMidity was running in server mode, I could run

aconnect [keyboard port (129:0 for vmpk)] 14:0
aconnect 14:0 128:0

and I could play the keyboard and get sound. But now, a while after upgrading to trusty, I tried to do that, and didn't get any sound. TiMidity itself still plays files fine, but if I try to play them with aplaymidi, I still just get silence. Oddly, the midi files are clearly being read. When I ran (where 130:0 was vmpk's input port)

aplaymidi -p 130:0 ~/path/to/midi.mid

vmpk was highlighting notes on the piano as if it were playing the midi. One time I tried this, TiMidity (?) very briefly played a fraction of a second of the first chord of my song before everything went silent and vmpk just highlighted the first voice on the keyboard as usual.

Now the weirdest part of this is that probably about 40% of the time, when I've played at least one note with either aplaymidi or vmpk, when I run

aconnect -x

I get a sudden burst of a note or chord from my speakers (that is, if I played one note, I get a note; if I played multiple sequential notes, they turn into a chord), as if the notes were being queued up but not being played and that somehow liberated them. I have no idea what's going on there.

A little while ago I remember having a problem with Audacity playing wav files sped up and also locking up if I tried to pause it, which it stopped doing when I set the audio devices to the actual audio devices rather than pulse. But now when I checked again, it's doing the opposite: it won't play audio at all and/or acts weirdly if I don't set the audio devices to pulse, and either way will very occasionally randomly do the speeding up thing regardless.

Oddly in the midst of what's looking like a pretty screwed up sound system, sound in VLC and Firefox has been working fine and if I play a wav file with

aplay ~/path/to/sound.wav

that works fine too.

Any idea what I could do to figure out what's wrong with ALSA and/or fix it?

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