the pot is definitely wired wrong.
what he probably did is turn the pot into a variable resistance for current output dacs.
This would then require all the extra voltage gain.
the whole input section needs to be re-wired.
will draw up what I think it should be when I get home.
the 4 resistors to ground by the xlr input jacks. 2 of them are 49.9k ?? . R40,R47
What are the other 2.R37,R42
the 4 resistors from the pot to the input fets are 2.2k?R9,R10,R11,R12
the 4 resistors on the bottom of the board, what is the value?
the schematic I did showed only one channel. If you replace the 154k resistors
with 100k, you have to replace a total of 8 resistors, 4 for each channel.