which is the OP amp ? or am i been thickIt could probably be an issue with the amplifier ICs. It could have gone bad. Too much volume can also cause some distortion. If you’re able to find the amp, check if the amp ICs get hot, if they do get scorching hot, that means that they have gone bad. The op-amp could also be an issue.
so found the issue , its my STD Connect PCB in the bottom of the cab , only issue now is i cant get a replacement, did fine a seller on Ebay who wont ship to the UK , so if anybody will sell me
NAMCO BANDAI STD Connect PCB Arcade Parts 8523960201 i be very happy