How to convert .mmf audio to .mp4 format.
As far as we know, converting Synthetic Music Mobile Application Files directly to MPEG-4 Videos (.mmf to .mp4 conversion) is not possible, at least not without a slight workaround.
You can use the VLC Media Player to convert your MMF file to a more common audio format, such as WAV. All you need to do then is to convert WAV to MP4, which can be done using numerous media editing programs or (online) conversion tools.
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