Sony D-NF420 Operating Instructions Manual page 34

Symptom
Even though you have not selected
"BOOKMARK,"
flashes.
Play stopped abruptly.
The TIMER function is canceled.
You cannot operate the player,
and a sequence of 8 numbers or
letters appear on the display of the
CD player.
Radio
Symptom
The radio is weak or has poor
quality.
Others
Symptom
When closing the lid of the CD
player, the CD starts to rotate.
34
Cause and/or corrective action
 If you have selected a playback option other than
(Bookmark)
"BOOKMARK,"
 The off timer has been set. Change the setting of "TIMER" to
"OFF" (  page 24).
 The dry battery is used up completely. Replace the dry battery
with a new LR6 (size AA) alkaline battery (  page 10).
 The TIMER function for the CD is canceled if you start
listening to the radio.
 The TIMER function for the radio is canceled if you start
playing a CD.
 This phenomenon may occur, depending on the CD you are
using. Remove all power sources, and then insert the battery
or reconnect the AC power adaptor. Try to operate the player
again. If the problem persists, consult your nearest Sony dealer.
Cause and/or corrective action
 Replace the battery with a new LR6 (size AA) alkaline battery
(  page 10).
 Move the CD player away from electric appliances (TVs, PCs,
etc.)
 Keep the AC power adaptor away from the CD player.
Cause and/or corrective action
 The player is reading the information on the CD, not
malfunctioning.
(Bookmark) flashes.