Am 03.10.19 um 01:04 schrieb Philippe GARCIA-ORTUNO: Sounds like seq24 is sending MIDI clock messages to your MIDI output, where the Tempest is connected too. You should be able to change this in the options window of seq24. It is also maybe acting as the JACK "timebase master", i.e. setting the tempo information for JACK transport clients. I'm not sure, though, whether seq24 does this. If not, some other JACK client must be doing this, and seq24 is adapting its internal tempo to it, as soon as it is set to follow JACK transport. What other JACK programs do you have running? You can use the jack_transport console tool to act as a timebase master (overrides any existing timebase master) and set the tempo: $ jack_transport AFAICS, jack_transport does not support setting the meter (beats-per-bar and beat-length) to something other than 4/4, For that you'd need another program, e.g. Carla, Ardour, etc. I also wrote a simple Python script (based on the jackclient-python library), which supports providing the tempo and meter. https://github.com/SpotlightKid/jack-audio-tools/blob/master/transport/time… The script is not a real-time safe solution, but is nice for testing. Chris