Hello, i've a problem with my a/v board.
The problem is on the board because when i put the wrong board in an other pinball the problem follows the wrong board and vice versa when i put a good a/v board in the bad pinball, the pin plays good and everything goes right.
The problem is that the wrong a/v bord has a sound issue. The display works great. When i start the pinball, there is no ''bong'' when booting and it takes more time than initial and after booting, the display indicate ''sound board interface error''
The ribbon cables were checked, the connectors J601, J602 were checked (at root for oxydation), the trace were checked, i've tested U4, 9, 10, 11, 12, 13, 14, 25 with the DMM and compare the values to the other ''good'' board and it's ok
I've also checked the trace for the roms sockets ans they are good. I take the functionning roms to put them on the board.

I'm out of ideas where to check now...
Could you help me to fix that ?