Sound Quality is Bad Only when CD is Played (Volume is Too Low) [10/2013 - ]: Procedure

REPLACE CD AND RECHECK
1. Replace the CD with a known good one and check that the malfunction disappears.
  OK
  
  Malfunction disappears.
NG → See step 2

OK → END
REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to REMOVAL [10/2013 - ]