hi Leatherneck:
I have a nice Oppo BDP-83SE, and I have also found this to be true... most discs play fine (smooth, quiet, and vibration-free when I hold the cabinet)... however, some (quite a few) discs cause vibration, mainly those from the library or rentals, and I have pretty well confirmed that they cause vibration because they are a wee bit unbalanced in the horizontal plane(not warped), due to the stickers, barcodes, clear lamination, etc. that are sometime stuck ontop of these discs... I've proven this by taking a "good" CD, sticking a short piece of masking tape off to one side (to create a small imbalance), and then playing it... sure, enough, I start to a get a vibration right away... adding more tape makes it worse, removing the tape removes the problem... Oppo is willing to take in my unit (at my ship cost + hassle and risk of ship damage...), HOWEVER, if this is a problem inherent to *all* 83s or 83SEs, then they won't actually be able to fix or change anything, and it will be a big waste of time... Q: what ended up happening with your unit?... did you send it back and get it fixed or ???... can anyone else comment, or better still, try the masking tape test and report back with your findings here?.. thank you!