Mazda 2010 Mazda6 Manual page 271

Interior Comfort
Audio System
NOTE
The displayable number of characters is
limited. If the number of characters, including
the file extension (.mp3/.wma), exceeds 32
characters, it may not be fully displayed.
Message display
If CHECK CD is displayed, it means
that there is some CD malfunction. Check
the CD for damage, dirt, or smudges, and
then properly reinsert. If the message
appears again, take the unit to an
Authorized Mazda Dealer for service.
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