[QUOTE]Originally posted by newawe:
[B]HI
I have problems with my Roland. While I am playing, the piano gets detuned...

Maybe that the aftertouch controlls your pitch or the velocity is set to conroll pitch. I have read that sometimes a stop of a sequenced song maps the controllers like this and have experienced the same as well.
Try to reset the controller in your Sequencer program or the whole midi stuff and see what will happen.
BTW could someone help me with that noise problem on the main outs??