[ALUG] MPC playback or file converter

Hi So I have this headless Debian machine serving miniDLNA on my network. There's good few hundred GB files in its library but I have a problematic bunch too. A very old cache of mpc files that don't want to play. Does anyone have a way to either force miniDLNA to transcode the files on the fly or to convert those file in place (preferably retaining files structure). Cheers, Bart