Emu XL-7 & MP-7 User's Group

I think my command station is broken but I cant imagine why or how. I 
got it used and it looks fine and seems to be in great shape, however 
It does things that I can't explain and there seems to be no 
resolution. Drum patters are off, like there are slight timing 
problems when playing them back, sometimes a chanel will just decide 
to have the arpagiator on and there is no way to make it stop, just 
now i was making a very simple snare pattern and when i played it back 
it for some reason wont play the snare sound from the patch i have 
set, but instead replaces it with the same sound as the bass drum from 
a different chanel! Even though the patch is totally different. Whats 
wrong with the thing? Am i crazy or is it?
If any of you have any idea what might be wrong with it please help me 
out ebcause this is so frusterating.
Have any of you had any similar problems?
I am going to ebay the thing if I cant get it to work right.
thanks