My Onkyo have had difficulties in reading some CD's. This error
particularly occured when reading the index on some CD's (usually
cheap recordable ones).
After disassembling my DX-7711, I wondered why the factory had mounted
two felt rings. I guessed that the only function these rings had,
was to protect the laserhead when it was sliding towards the center
of the CD.
When there are two rings mounted, then the laserhead
can't reach the center of some CD's - and that was the fault on my
DX-7711. The instruction below shows how to check and modify
the DX-7711 to remove this problem.