Stupid 5150 question.

the footwitch is a little wierd, couldnt get my marshall to work with it...
however, if you use a one button footswitch and pull the lead half way out, hey presto it works
 
mine didnt oddly, the light changed but the channel didnt....
very odd!works now, and i sure as hell aint using the peavy footswitch, amp didnt come with one, and im not paying good money for a bit of tupperware