Quoted from Schwaggs:
Cool, then there is only a potential problem with U17. Is that by chance socketed? If so, check out the solder job on that socket and if another 6118 is socketed, it would be a simple test to swap them and see if the problem follows the chip.
I dont believe it is but I will check when I get home. So, I'm used to automotive/motorcycle diagrams... the hollow line after the diodes from j5 goes directly to u19 and u20. The thin lines that branch to u17 and u18 are connected to the hollow line? I was assuming there would be dots if they were and they just passed under on the diagram... thank you for helping me narrow this down