Sony NF421 User Manual

Troubleshooting

Should any problem persist after you have checked these symptoms, consult your nearest Sony 
dealer.

Sound

The volume does not increase 

even if you press VOL + 

repeatedly.

 “AVLS” is set to “ON.”  Set it to “OFF” ( page 24).

No sound, or noise is heard.

 Connect the headphones/earphones plugs firmly.
 The plugs are dirty.  Clean the headphones/earphones plugs 

with a dry soft cloth periodically.

A rustling noise is heard from 

the CD.

 Close the lid of the battery compartment firmly ( page 10).

SOUND items cannot be set up.

 “POWER SAVE” is set to “ON.”  Set it to “OFF” ( page 25).

Operation/Playback

The playing time is too short.  The 

CD does not play.

 Check that you are using an alkaline battery and not a 

manganese battery.

 Replace the dry battery with a new LR6 (size AA) alkaline 

battery (

 page 10).

Certain tracks cannot be played. 

 You tried to play files saved in a format that is not compatible 

with this player (

 page 5).

 Change the setting of “CD-EXTRA” in the OPTION menu. 

You may play your CD (

 page 25).

“Low Battery” appears on the 

display, and the CD does not play.

 Replace the dry battery with a new LR6 (size AA) alkaline 

battery (

 page 10). 

“Hi DC in” appears on the display.

 An AC power adaptor which is rated higher than the one 

supplied or recommended is being used.  Use only the supplied 
AC power adaptor or the car battery cord recommended in 
“Optional Accessories” (

 page 36).

D-NF420/NF421.GB.2-318-768-12(1)