[SOLVED] Weird pedal noise

[Kirfew]

Hey guys, I've just built a DAM Meathead replica, and it sort of works.
I can switch between the bypassed signal and the effected signal correctly, and the fuzz works (as does its control), but when I plug into my power supply there is a RIDICULOUSLY loud hum on both the bypassed and effected modes. Also, the fuzz control affects the volume of the bypassed signal in addition to the fuzz signal, and when turned up to maximum it causes a big drop in treble.
Anyone know how to remedy this?
Here's the schematic btw:
http://tagboardeffects.blogspot.com/2010/10/dam-meathead.html

Fixed:
I was using an SPDT switch, so the outputs were sharing the potentiometer.
Also the noise was caused by my power supply being extremely dodgy.