Sony CDX-GT620U Operating Instructions Manual page 21

If these solutions do not help improve the situation,
consult your nearest Sony dealer.
If you take the unit to be repaired because of CD
playback trouble, bring the disc that was used at the
time the problem began.
Support site
If you have any questions or for the latest
support information on this product, please
visit the web site below:
http://esupport.sony.com
http://www.sony.com/xplod
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