I just upgraded to 0.8.6. I'm finding that I'm unable to seek in mp4 (h.264+mp4a) files beyond the amount of time since I installed. Meaning, 15 minutes after I installed 0.8.6 I could seek within any mp4 file from 0 to 15 minutes but beyond that the video freezes and audio turns off. Now it's been 60 minutes since I installed 0.8.6 and I can seek within all my mp4 files from 0 to 60 minutes but beyond that no luck. I tried about a dozen files. Rebooting made no difference, only the time since I installed.
This is showing up identically on 2 computers or I would never have figured out the correlation. I've seen it before in 0.8.6 beta releases, and maybe in 0.8.5 as well, but never made the connection (problem goes away on its own after 2 hours since I don't have any h.264 files longer than that).
After I've been typing this note I tried yet another different file and now I can seek up to 70 minutes...