Pioneer XSP550 Stack system - CD problems.

[Turnip]

Hi Folks,

   Have one of these where initially only radio section seemed no go due to a partly duff relay in Power/Amp. That replaced, discovered CD would play 4 tracks then stop with hunting sounds from laser. Eject, and other CD buttons had no effect until unplugged to cool for a while. Symptoms then repeated.

   Any thoughts ? - Chris