Question about Denon 2910 read errors


I just got this unit from ebay. Sounds great and I love it. But it seems to be overly sensitive and has problems playing some of my DVDs and CDs. My budget DVD players had no problems reading any discs.

Is there anything I can do about it? Any repair services out there to fix this problem? Can this be easily fixed?
spareribs
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Update:

So far, every CD played. If I had a problem, I would turn it off and turn it back on and it would play. It seems to have a problem with burned DVDs but not all of them. I haven't tried original DVDs yet but I assume it will have better success in reading.

Soundwise, it's excellent and working.
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