I have attached pictures of the machine and the eprom chipset on the MPU board. My 504B MPU board does not have any sound SIMM on it and neither did the original 502A board. So this is basically where I'm stuck with troubleshooting and looking for some expertise with this problem. Checked the volume level is set to 8 in the software. I ordered a tested inline amp board and replaced the original and I still have no sound. Checked 12V power going to the amp board and it is good. Checked speaker connections from the back plane board to the inline amp and to the speakers. I have swapped wiring from the left to the right speaker but still no sound. Everything else is working fine and there are no errors. The static got more frequent and progressively worse until there was no sound at all coming from the machine. It occurred when idle and during game play. About a week later I noticed some static noise coming from the left speaker. The sound from the machine only played from the top left speaker but I read that was normal from various posts to this site. So everything was working and I was playing the machine a lot. Fixed that issue by replacing the coin comparitor. This bought the machine back to life and everything but the coin comparitor was working. I bought a 504B board and inserted all of the eproms from the original board. After reading posts on here and with a little help from a friend of a friend we determined that the MPU board had the dreaded Varta battery damage. The machine was DOA, but I only paid $130 for it. I purchased and Triple Double Diamond 3 reel mechanical slant top at a garage sale about a month ago. I can't find any previous topic related to my specific machine or issue so here goes.

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