(Re-directing the discussion to the mailing list again.)
Am 03.10.19 um 15:03 schrieb Philippe GARCIA-ORTUNO:
Yesterday I made a test to connect seq24 (in seq24
send the clock to
midi Throught and then connect midi Trought to Ardour MMC,
Ardour+seq24+Tempest played well at 120).
So is Ardour normally involved in your setup? Can you describe exactly,
which (audio) software you are running and what is connected where and
to what (audio and midi, ALSA, JACK and hardware MIDI connections)? Try
to create a minimal setup, which still exhibits the problem.