So I just installed a Phat DAC onto my Raspberry Pi3. While audio from Chromium is completely fine, the audio from omxplayer is messed up. When I try to play a video, the video plays much faster than it should and the audio output is simply static-like noise. However, if I skip around multiple times with the arrow keys, then all of a sudden it falls into working order with beautiful sound and proper-speed video.
Any ideas what might cause this? I'm running on a fully up to date install of Raspian, and I used the official setup script for the Phat DAC.
Update: omxplayer works fine in the bare terminal, it's only behaving weirdly if I run it with the GUI desktop environment loaded. What the heck?