Use bmwconv command line tool available for free to transform BMW iDrive multimedia data file with BR3 file extension to MP3 audio. There is also the BRx Konverter that can be used for the same thing as well.
Convert BMW iDrive multimedia data to Compressed audio and music file, mp3 songs or ringtones.
We found 3 software records in the database related to .br3 to .mp3 file format conversion.
Microsoft Windows software - convert br3 to mp3 on Windows
A command line converter for BMW multimedia files
Convert from br3 file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned br3 to mp3. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
A BRX to audio converter
Apple macOS / Mac OS X software - convert br3 to mp3 on OS X
An audio data converter for Mac used to convert audio from BMW car system to MP3, WMA and MP4