Unwanted notes played

jpg posted Jun 26 '16, 21:08:

When I play several notes very quickly, some notes are played again several times very erratically.

I logged into my rasberry 2 by ssh (login:root, passwd:root), killed the samplerbox process (in fact python), and ran it manually to see the messages of the software (samplerbox.sh script in SamplerBox directory).

  1. I used a midi monitor software to see what happens from the midi point of view. It is not a "Running status error" because all the notes on/off are correct (see http://www.samplerbox.org/forum/46 and http://www.samplerbox.org/forum/146)

  2. I added some "print" message in the MidiCallback function in samplerbox.py file to see what happens when the script is launched. NB. It needs to mount sdcard rw or copy the SampleBox and the pyaudio directories in the /media and modifying the samplerbox.sh accordingly.

Keyboards tested : microkorg XL or Axiom pro 61, all connected by usb

The microkorg XL produces many "MidiInAlsa::alsaMidiHandler: unknown MIDI input error!" messages.
It seems to be a problem in rtMidi python module https://github.com/danomatika/ofxMidi/issues/19 and https://recordnotfound.com/rtmidi-python-superquadratic-94558/issues#closedIssues

The problem is that the microkorg produces many clock messages, especially when the tempo is max! I think the samplerbox is overloaded by these messages and misinterprets some note on/off messages. Sometimes, I can have a "Segmentation fault" and the script crashes.

The Axiom pro 61 does not produce some clock messages and everything goes well.
I have got some "MidiInAlsa::alsaMidiHandler: unknown MIDI input error!" messages when I played very quickly some fast chords/notes but no erratic notes are played.

So the problem does not seem to be in the samplerbox script but in the rtmidi module.


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