MP4 alac
 

I have some audio files that WINAMP identifies as MP4 alac.
Is there a way to play them on WINAMP?

Those are proprietary Apple Lossless files. They cannot be played by anything else besides iTunes/Quicktime.

But all is not lost.

For there is an ALAC decoder plugin for dBPowerAMP Music Converter, so they can be converted into a more usable format (such as FLAC, WavPack or Monkey's Audio).