I installed Ardour 3.0.0 build 14207 on UbuntuStudio 12.04.
I try to record midi tracks. Everything is working fine during the recording (I hear what I’m playing), but nothing is played back. Even the meter on the mixer does not show a signal.
Is it a configuration problem or somebody else have the same problems ?
From your picture I see you have a midi virtual instrument on the track, though it is not visible. Since the meter shows no signal on playback perhaps the instrument plugin is disabled (green “LED” on the plugin not green - click to enable/disable) or if the plugin is configured to use a different midi channel than the midi notes in the track (unlikely).