I just finished building my 3rd ProCo Rat replica today. There are 2 problems:

1. The output volume is very low, half the volume of the bypass signal with the knob turned all the way up.
2. Sound is very fuzzy and compressed even on the lower gain settings.

Here's the voltage chart:

IC1:

P1: 8.32V
P2: 4.19V
P3: 2.04V
P4: 0
P5: 0
P6: 4.20V
P7: 8.42V
P8: 8.32V

..and schematic:
http://www.generalguitargadgets.com/pdf/ggg_rodent_sc.pdf

Compared with my other Rat clones all voltages are ok except the P3 and P8, they should be somewhere around 4.5 volts.

Any ideas?