No MIDI output when playing back MIDI track

While I can record midi from my synthesizer, I am not able to play back midi tracks to the device. While the track gets recorded and the VU meter in the MIDI tracks mixer strip shows that something is happening when I am playing back, nothing goes out to the ALSA midi sequencer port (I checked with Gmidimonitor, there is no midi transmitted from that port at all).

Hi are you using jack or alsa backend?
How is the midi route made?

Is there a Synth plugin on the MIDI track?

If so, remove it (in Ardour’s Mixer window), or create a MIDI track without an instrument (select “-None-” in the instrument dropdown).

If that’s not the case, check with Ardour’s MIDI monitor to try to narrow things down:

  • Ardour Menu > Window > MIDI Tracer allows to check ports (similar to gmidimonitor) from Ardour’s side. Select the output port if the given MIDI track. If it shows data, then it’s probably not connected to the right hardware port…
  • Ardour also comes with a plugin “a-MIDI Monitor” that can be directly added to a track, printing MIDI data that flows through it.

Are you using JACK or Ardour’s built-in ALSA backend?