Ford Vehicle Owner's Manual page 154

If play does not begin after the CD button is
pushed:
The radio is not on.
The unit is in the stop mode.
Moisture may have condensed on the lenses
within the unit. If this occurs, remove the CD
magazine and wait approximately an hour
until the moisture evaporates.
If the sound skips:
Badly scratched discs or extremely rough
roads will cause the sound to skip. Skipping
will not damage the disc player or scratch the
discs.
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