Well, if it was a memory problem, you'd get blue-screens. Maybe the Hotline Miami thing is completely independent of your audio problem.

Honestly, these are the most frustrating problems to track down. If you did get a real blue screen, we could look at the diagnostics. Can you go to the Sound section in the Control panel, and find your playback device, and tell me what it is configured for? Probably stereo?

There are a lot of other things that could contribute. You could be drawing too much power (try a different outlet, if it was a desktop I'd suggest a different power supply). It could be the specific playback device (try different speakers). The Chrome/Firefox Youtube stuff could be a corrupt/old/anything Flash installation, Flash is awful (uninstall flash, run cclean again, then reinstall flash). Who knows, man. What disk checker did you use? chkdsk?

Do you get input lag (like mouse/keyboard delay) for the moments when it happens?

Did you try beating the laptop angrily with your penis?