That was some creative thinking Oren
I actually solved the problem, for future reference : Ardour wants echo back on his MTC
Just for fun, I tried your solution Oren and it actually works.
Nice setup, you record midi out from the groovebox in Rosegarden and audio out in Ardour, just like you said
k
I haven't got nearly that far, Kara, but the direction I would go is to have both Rosegarden and Ardour running. Set the Ardour "positional sync source" to MTC or JACK (which ever syncs it best to Rosegarden), and turn off the Ardour "time master". Your Yamaha has already shown itself capable of triggering Rosegarden, and Rosegarden will in turn trigger Ardour.
If that set-up doesn't work, set Ardour "positional sync source" to JACK and make Ardour the "time master". This may link the transport controls of all three devices through JACK (just the way it does with Hydrogen).
Rosegarden will record the MIDI events, and Ardour will record the audio output.
I couldn't test it here (no keyboard), but the theory works....