Flash audio hum

These boards will have some hum but it should be inaudible unless you get your ear up to the speaker or turn the volume way up. If two borads have identical type hum its probably not the sound board.

I had a time warp where the power board square 6 pin (only 2 wires used), where ground comes in, burn up and cause the nasty hum out of the sound board. Even tho the sound board has its own transformer tap and power supply, a ground problem on the main power supply must be able get noise into the sound board. Try reseating that plug with the power off and see if the hum changes.

Check the flash manual page 21 and 22, these pages are reversed in the IPDB scan pdf file. It should not apply to a type 2 sound board but they have some notes about noise you may want to read.

So the guy removes the center tap ground connector pin from the transformer power input it reduces the hum. Wouldn't that just mean he has a ground potential issue at the place where grounds actually come together? That hum is not norrmal on sys3-6 games. Sys 11, yes to some extent.

I have had that hum in system 6 game firepower(similar sound) and I want to say the 6pin square shaped ground plug on the power board was the caused. Can't remember exactly but pretty sure fiddling with that plug made the hum go in and out. Repin it made the hum go away.