Debugging a mod'd EH Small Clone

[closetmonster.]

Hey folks!

I picked up an EH Small Clone for a steal from a local shop, and have been tinkering around with some of my pedals so I decided to give this one a dive.

I have been following the tutorial posted here:
http://experimentalistsanonymous.com/board/index.php?topic=1578.0

Everything has been going swimmingly, and I think I am very close to having the sound I want from it. The only issue I've had with it thus far is to do with the tremolo mod. Even when the pot is not engaged, I get a wash of high frequency noise in time with the LFO. I have tried changing the the output resistor from 10k to 15k, and I get slightly less noise but the effect of the tremolo is also a bit less... effective 

I have considered putting the tremolo circuit on a switch, but I don't want to drill more holes in the enclosure than I need to.

Any input would be greatly appreciated. I have done a few mods, but at this point I am basically just poking in the dark.

Cheers,
Nick.