There are various sounds added to R2 and Chewie's game on the mono mix and the SE, but not in the '93 version. I could go back and compare them again to make sure, but I'm quite positive they are exactly the same.
But what about on the GOUT version? My understanding is they weren't on the 93 version but were added on the GOUT. (The metallic clicks when Chewie and r2 push buttons playing holochess.)