Yamaha DTXpress/DTXplorer/DTXtreme

Hi there,

New poster, hope someone can help me...When I set up a pad song it 
seems to change the voices I have assigned to piano notes. All I 
want to do is set up some simple percussion one or two bar loops. I 
create them fine...put them in as a pad song and initially they 
work, but if I change the kit when I come back to it the sounds have 
changes to piano sounds...any ideas???

Grahame