Yamaha DTXpress/DTXplorer/DTXtreme

First of all. let me say that I'm verry happy with my DTXpress III 
and that this is my first edrum so I know verry little and that is 
the reason for this post.OK when I play along a song that is in the 
brain I can't ear my playing .I know there is a mute drum fonction 
(shift)+ page up and I use it a lot but what I want to do is play 
along the drum part and others. Hope you will understand what I need.

Thanks
tommy