I used this... 7.5VAC/400mA AC adapter for the Hum Debugger ...to power a standard 9VDC pedal accidentally (it looks very similar to one of my 500mA 9VDC adapters). I'm not sure which pedal it was (but all the pedals are 9VDC) as it was among a bunch on a power strip and I only noticed when I rearranged my board and unplugged the wall warts. Could I have done damage to one of the pedals? I've started to notice an annoying squeeking noise happening with my ISP Decimator G-string II noise gate whenever it closes the gate, but only really when using distortion -- I'm worried maybe this pedal got damaged or something as it is my most expensive pedal. Thoughts? I think all my pedals still appear to work, although I haven't actively tested all of them.