Has anyone else had problems with the model selector knob on their M5? I've had two go out on me. Basically what happens is I can press in the switch to change the type of effect, but it doesn't do anything, but turning the knob will change the model. I bought it at guitar center and got the pro coverage so they replace it for me, but it still sucks to have a pedal that isn't reliable. Does anybody have a fix for this? I've thought about sending it in to get modded, but if I do that and it breaks again, I'm pretty much screwed. Any suggestions?