So I tested it out. When playing a video via VLC Player using USB input; there is a slight delay in sound, as if a few milliseconds behind. When using Optical input, there is no such delay. Playing youtube the delay in USB seems less apparent compared to playing a video file on the computer, however when played via Optical there is no sound delay. I dont have any videogames installed on my computer right now! I'll have to try another time, though i suspect the same may be true for videogames as well.