Denon DVD-2910 excessive vibration?

I would venture to guess, that if your Denon unit is consistantly vibrating significantly on most or all disks, that would signify a problem with the transport unit. If it just happens on the occasional disk and is not shaking to the point that you can actually hear it, then that would probably be within tolerance. As I said, my machine just vibrates on a few disks, most are fine so that would indicate to me that I don't have a problem with the transport. Also depends on your interpretation of vibration. A slight vibration when the disk is spinning I believe is normal.
If anyone can actually identify a known problem with the 2910 and report the fix, please do.

I don't put any credence in the "off-center disc" theory.

My Yamaha S1500 played perfectly for seven months, then, started with the vibration business. It does it only on DVD and only after the unit has played a few discs previously. Sometimes a disc that has "vibrated" will later play OK. I think it's a lousy motor or motor bearings.

I would not argue that Theduke's player does not have a problem. Or that others who have posted describing their issues with their players may not actually have mechanical problems. I am just describing the experience that I had with my player. I find that 3 or 4 of my CDs consistantly vibrate. I made copies of a couple of them and the copies don't vibrate at all. DVDs don't vibrate nor do my SACDs. This dosn't change if the player is cold or warm or how many CDs I have played before. So I put out the theory that it may be the disks being out of balance that is causing it. The mscience article I mentioned above seems to support that.

When shopping for a player a year ago, I tried the Denon in the store. It vibrated so badly, I thought it was going to jump off the shelf. I passed it by. Wound up with a Daewoo for 50 clams. It does everything well.

Just bought a new 2910.
It started whining (high pitched sound) on track three.
The noise, a mechanical resonance, lasted about two minutes.
The whine really stood out whenever the music had a similar frequency (a glaring distortion).
I tried putting some sorbothane pucks on the player but it didn't help.
It was late night listening (low volume) which may be why I noticed.
Thinking I may have to return this pup...