I just installed the VLC app on my Xbox 1 and when I try to fast forward more than about 10 min through a show the video freezes but the audio goes to the proper position. I'm playing .mkv files and have not tried any other type yet.
The only way I'm able to correct the freeze is by skipping to the next video then going back, or by exiting and restarting the file.
It's not a huge problem just annoying to fast forward in short bursts instead of going to the point I'm looking for.