[pgaddict]

I occasionally see stutters too, even with Full HD video. Or more precisely, mplayer complained about slowness and having to drop frames.

It often helped to actually give the VM more cores (not just the default 2), but sometimes it was due to some weirdo codec/quality setting, and recoding the video just solved it. Sometimes switching to vlc (from mplayer) helped. Other times it was simply due to the sys-usb vm being overloaded.