Ground loop?

[Leema]

I have no idea if this is a ground loop problem, interferance or a faulty cap on the power section of my board but hopefully someone will be able to shed some light on the matter  

I have built an Insanity Box from diystompboxes.com. It's really cool (now i've got it working ) It works fine on it's own but that's not the purpose i have built it to serve.....

I have installed it inside a Boss ME-X and added a stomp to turn it on. It takes it's power from one of the ME-X boards which supplies a 9V power adapter socket used for plugging in external effects/loops. The ME-X has 3 such loops with their own send/return jack sockets.

I have soldered the input of the IB to the tip joint of one of these loop sends and the output of the IB to the tip joint of the return socket.

Now this is where i think the problem lies.....
The solder joints for the ME-X send/return are linked together and are also linked to the ground circuit of the ME-X. I have taken a wire from a point on the ME-X ground circuit and connected it to the ground of the IB circuit (which also has a ground coming from a power circuit).

Is this what is causing the high pitched noise even when the IB is turned off? Can this be cured with a cap somwhere? The noise is relatively quiet but none the less-it's audible and the only way to stop it is to throw the ME-X into bypass mode. Turning the guitar down doesn't help.

Eeek!

[niftydog]

The phrases "high pitched noise" and "ground loop" don't go together.

The 9V power socket from the ME-X is providing a ground to the IB.  Leave the "signal ground" (send/return sockets) UNCONNECTED and it should still work.  This will ensure that you don't have a ground loop.  1 ground connection = no loop!

Try a couple of things to narrow it down.

power the IB from an external power supply.  (you may or may not need to reconnect the "signal ground")  Sound gone?  Suspect the ME-X power supply.

Now, take the output of the IB and instead of putting it into the "return" jack, take it to your amp input.  Is the sound coming from the IB or the ME-X?

I can't find any specs on the ME-X power supply, but it may be struggling to provide enough to the IB.  Just a guess...