Need help with Sonic Distortion

[ethniccheese]

I've been working on the Sonic Distortion from J.D. Sleep's GGG site for some time now.  I finally found a capacitor on the parts layout, C6, that was backwards from the schematic.  Before that I barely got any sound out of the pedal.  Now I get a good strong signal, however, the signal isn't changed from the original.  The tone section works, but the drive pot doesn't do anything.  The diodes aren't clipping.

I have replaced almost every part on this board (some 4-5 times!!).  I'm getting good voltages on my transistor and my opamp.  The diodes are oriented the correct way.  I have checked for cold solder joints and have come up empty handed.  I built the audio probe from Geo and probed my little heart out and the signal never clips.  I even used my oscilloscope and found nothing clipping.  I am at the limit of my knowledge and resources and don't know what to try next.

Anyone have any experience with this pedal?  Any suggestions?