S5500 sram clear afterwards

[61Wally]

Good evening to ALL. I replaced the battery on a S5500 and there’s a couple of issues I’m having.l The machine accepts bills, but NO credits appear on the display. The next is there’s NO sound at All. I noticed on my blazing 7’s there’s an audio board mounted on the the inside wall and nothing on this One, I haven’t seen this before. If I take the boards and swap them, both machines just continue to have the reels keep spinning when I turn them on. When I put them back to Original machines they play fine with the exception of No sound o the “7777” machine.
The board with blue tape on the chips is the one that has No sound.
The backplane wiring doesn’t have One of the Black connectors. Any enlightenment on this would be appreciated in learning the differences.
The second board is the Blazing 7’s I tried swapping.

[Sunrise Side]

The volume control is on the front of the MPU , the left side. Check the BV harness at the backplane and see if you have a GREY wire in the position show in the picture.

[a69mopar]

When you swap the boards. Hold the change/service button while you power up. Continue to hold until the reels align and start to shake.  This should calibrate the reels to the board.
Thanks,  Wayne