emulatorII-list

Ok, I've been playing heaps on my EII (love it), and now i've been 
struck by a real pain in the arse bug.

occasionally (and when it does do it, it's pretty constant) the 
output of my EII drops / dissapears / comes back, like someone 
playing with a bad connection.

-I've tried the separate outs, and they all drop in the same way.

-It does it even if there is no contact with the keyboard (ie, i'm 
not playing it).. If i run a sequence, it'll drop out.

HELP.

I'm pretty good / technical, so i was hoping for some guidance. 
I've heard the powersupply can be a bit flakey, should i start by 
checking the output rails?

Cheers

Mike