Possible MPV/memory bug in tabbed-windows branch

[ahuston-0]

After switching everything over to tabs in the tabbed-windows branch, testVideo and testAudio no longer produce any output. There are no obvious errors from Grail or MPV that are being emitted, but it is suspected to be a memory bug.

[ahuston-0]

Turns out that it was an issue to do with the fact that we're relying on the frame-rate to determine the update time. We fixed it by setting the framerate to 0 (continuous updates and renders), but we need to determine an alternate method of playing audio without forcing redraws.

[hydrodog]

Not a memory issue. Audio and video require animation to be on in order to act. For video, that isn't bad. For audio, we need to create a background thread so video need not be animated in order to play sounds