Would you guys consider adding .mkv file support to your list of supported video formats. MKV has robust support for FLAC audio which would be handy.
Love what you guys have done so far tho. Great work
Hi there!
If importing MKV files into Live is not possible, then this is a limitation of Live and not of Videosync. Once Live supports it, then we can in turn see if we can support it with Videosync.
On this page of the Ableton Knowledge Base they recommend using the .mov and .mp4 containers, but .mkv isn’t mentioned. So I think your best bet is to file this feature request with Ableton 
Thanks for the info 
I had a play about yesterday trying to create some music videos for use with show sync.
I settled on using .mov files as you can encode the audio stream as a wav.
Also, the free version of Davinciresolve has pretty good export options regarding .mov files and audio formats. So if anyone else is looking for a good free program to make music video for Live/Showsync, i can recommend it.