I actually got a pair of headphones with the ground line grounded, and went testing with the 'live' wire around the resistor network in that area. with some line tracing i traced back the signal to the point the signal sounded crackly, and then just replaced the surface mount resistors! Thankfully it was the final stage output resistors, cause otherwise it woulda been too complex for me to fix probably.

Wasn't visibly obvious, tho the solder did look a little 'dry' didn't check the actual resistors cause the work lab has a stack of replacements (thanks www.energyintellect.com) so I just replaced em.