The people who created the MIDI file probably did not set a MIDI Control called Program Change.

The default on all MIDI channels is piano. You must edit the MIDI Code on the channel that plays piano.

First, go to measure 1, open the MIDI code view. Scan forword for something that looks like PC 000-000-001. If memory serves me corectly, if you change it to PC 000-000-129 and save this then you should have no problems.

I could be wrong about the MIDI code for drums, but you can always check your manual.

I hope this helps.

Cinda