[popcornmix]

Thanks a lot for pointing me into that direction! You were actually right, I had a USB MCE remote (like this one) connected to my Pi2 and when I cut the cord, the frame skipping had stopped completely. This also improved playback for other files of mine, e.g. 1080p with AC3 and passthrough, or streamed amazon videos.

Okay that's interesting. I wonder if you could try adding:

Code:

dtoverlay=lirc-rpi

to config.txt (with the USB dongle still removed) and confirm if that also stutters. You don't need actual lirc hardware - there are reports of just that option causing stuttering with OSMC.
That's what I'm trying to use to reproduce the issue, but I'm not seeing it in my debug environment so far.