See also:

Notes On Playing MP3/WMA Files
The radio can play MP3/WMAfiles; however, acceptable MP3/WMAfile recording media and formats are limited. When writing MP3/WMA files, pay attention to the following restrictions. ...

Tire Terminology And Definitions
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Supported MP3/WMA File Formats
The radio will recognize only files with the *.MP3/WMA extension as MP3/WMA files. Non-MP3/WMA files named with the *.MP3/WMA extension may cause playback problems. The radio is designed to reco ...