Hello everybody, this is my first post in this awesome forum. Been lurking for awhile and have picked up lots of great tips and information.

Mine is a complicated issue: I have an old non-status light SMM that I purchased of ebay about two years ago. Unfortunately, the thing has been giving me trouble since I received it. When I first got it, it was humming much like it is now; so I opened it up and discovered that a wire was loose and not connected. Through examining the board, I saw the remnants of where the wire was connected and simply re-soldered it and boom, problem solved… nice and quiet, awesome delay sounds, much better than my Ibanez AD9.

A couple of months later, I plugged the SMM in and to my surprise, this very-very loud hum blared through the speakers when I took the amp off standby. At first, I didn’t know what it was but through a simple diagnosis, I discovered it was indeed the SMM. It was not allowing any signal to pass through it, only this extremely loud buzz or hum. I assumed it was shorting out but I couldn’t figure out where. Needless to say, I got frustrated with it and it has been sitting on my shelf for about a year.

Recently, now that I have more free time, I have decided to once again attempt to repair it. This is where I come to you all for your expert knowledge. I took it apart to look at it a week ago, put it back together and plugged it in and oddly enough, that loud buzz sound is gone and it is once again allowing signal to pass through. Only problem is it still has an excessive hum (the hum is not nearly as bad as when it was not allowing signal to pass through). So, it is not shorting out anymore, but something is still not 100% right. All the wires appear to be connected to the best of my knowledge. Where can I start to diagnose what is causing the hum and solve this problem? Would it be helpful if I posted some pictures of the circuit board?

Thanks,
Dave