[1.9.10] Audio desync over time

[LordHDL]

My settings:

• 60 FPS
• 2000 Kbps video
• 128 Kbps audio
• 44 kHz sample rate
• 0 audio shift
• Syphon Inject Capture (on frame arrival)

I tried feeding audio through Soundflower (2ch) or built-in input, both result in the desync. The audio preview itself does not desync, but recordings and live streams do.

After some testing I've confirmed that the audio tempo is slightly slower than what it should be, causing the audio to lag behind. Probably related to #78 and #79.