You can try to change the settings in Capture settings and reduce the frequencies in "Audio format", or try to change the video settings (by reducing the "Output size", I don't think that colorspace is the cause..)..
Otherwise you can try to change the video rendering mode (CTRL+P -> Video -> Video rendering -> Rendering mode)
But you noticed anout of symc problem respect to the video you are watching or respect to a standard TV audio?
If the audio is out of sync respect to your standard TV then it's "normal".. well, normal for BSplayer, the problem has been reported in the MEGA bugs post
here 