Tech Help needed on ATARI RotJ Upright

HI All, I needed to pick your brain. I have an ATARI Return of the
Jedi that I recently picked up. I was told that there were NO problems
with any of the boards, and that it was in great conditon. Well, the
condition of the cabinet was nice, but there was a problem with the
boards. So far my emails to the previous owner, have gone unanswered.

Here's the problem that I was hoping to get some guidence on:
I noticed that there was a dull sound coming out of the right speaker.
I swaped the left speaker (which sounded fine) with the right speaker.
Still sounded dull on the rightr side regardless of which speaker was
being used and the left side was fine.
A friend suggested that I replace the AR board with a new one, which I
did. Same problem and I still get a dull sound out of the right side
speaker. You can hear speech, but when it comes to blasts, and
background music, it's still very dull, unlike the left side. Any
suggestions? PLEASE HELP!

-Gio

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