It says buffer is 50ms (Recomended). What should I set it to and why would this cause sync problems?
Which of the two settings I suggested you look at is set to 50ms? I suggested looking at two different settings.
As noted above, try setting it to a lower setting to see if that helps. I cannot recommend a specific setting as every audio device works a little differently. Try lowering it, and see.
As for why a buffer setting might cause sync problems, a buffer effectively adds a delay to audio to ensure that audio playback isn't interrupted by sudden shortfalls in the data stream. Some buffering is necessary, but if you have too large of a buffer it will affect a/v sync with external sources because JRiver has no way of knowing how fast external video (e.g. in Chrome) is playing. So the solution is to use the smallest buffers you can use without causing problems (too small buffers will cause crackling, sizzling, or drop outs).
In any case, don't worry about audio sync and messing with the buffers right now until you get your audio driver and device situation sorted out.
Glynor is, as usual, quite right. Get your basic output settings sorted, and then worry about the buffers.
