Audio tab
Your only option on this table is whether to mute all videos in the playlist or not. You can't currently specify audio on some videos are not on others.
You can also specify a volume level between 0 and 100. A volume of 0 is the same as mute. This doesn't change the system volume of the computer, but this can be useful if you have two video controls on screen and want audio from both of them at the same time. You can then set each video's volume separately.