Kaser BW - Manual (Page 23)

Troubleshooting
No power Check whether the battery installed properly and
has a charge.
No sound in the
earphone
Make sure the volume is not under 0 and the
earphone connecting.
Make sure the earphone is clean.
A corrupted MP3 may not play.
Unusual LCD screen text Make sure that you choose the right language.
Cannot download the
music normally
Check whether the USB connection is correct
Whether the driver installation is correct (Win98).
Check whether there is enough free memory.