Sony DSX-A50BT Operating Instructions Manual page 37

READ
 The unit is reading all track and album
information on the USB device.
– Wait until reading is complete and playback
starts automatically. Depending on the USB
device structure, it may take more than a
minute.
UNKNOWN
 Name or phone number cannot be displayed
when browsing phonebook or call history.
WITHHELD
 Phone number is hidden by caller.
If these solutions do not help improve the
situation, consult your nearest Sony dealer.
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