Sun Oct 18, 2015 10:12 pm by atc98092
uPnP has nothing to do with playing them. Serviio uses the DLNA standard. uPnP is a networking protocol.
I agree that conversion to MP3 would be most beneficial, as virtually everything can play them without transcoding. As far as how to do it, there should be hundreds of programs available for that. Handbrake can do it of course, as can FFMPEG from the command line. Someone could likely even offer a script to automate the entire thing, but I'm not familiar enough with FFMPEG to do it.
I just entered "convert m2v to mp3" into Google and came back with 430,000 returns. Find something for free and give it a try. Just watch for them wanting to install something you don't want. Often freeware includes "optional" software that is selected by default.

Dan
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