VIETA VPC55BT User Manual page 31

Under transferring mode, All the MP3/WMA operation is not functional, like file up / down,
Repeat, Random, and Intro etc.
The audio will remain recording by the unit system even MUTE function is activated
The Transferring will automatically stop if the storage device memory is less than 2MB
WARNING:
1. Never remove the USB Stick while recording or file transferring to USB Stick. It may damage
the USB Stick and sometimes will caused the unit system lock up.
2. It is not recommended to insert USB stick while recording is under progress to other
storage device. Always remember to stop the recording or after the recording is completed,
then insert the USB stick.
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