I'm in the process of moving my music to open source codecs and need to convert a big bunch of Apple Lossless files to FLAC. The problem is that the file extension of AA files (.M4A) isn't a good identifier since the lossy AAC codec uses the same extension (and obviously, I dont want to convert these to FLAC). Does anyone know of any batch that could identify the lossless files from a group of M4A files. Could dbpoweramp do this? Is there another way?