can you manually hit the switch by lifting up the pedal, and pushing the actual metal pushbutton switch? Maybe it just wore the felt to far to click it.

If not, The DTDP switches should swap right in, and are only like $6 or $8 bucks. I think that's what the 525Q uses, it has true bypass right?

open it up and have a look what kind of switch it is before you order.
"The fool doth think he is wise, but the wiseman knows himself to be a fool." - W.S.
amp clips
amp vids