When playing and embedding Youtube videos add the following code directly after your youtube url.
&fmt=6 (HQ videos with mono sound.)
&fmt=18 (HQ videos with stereo sound.)
&fmt=22 (HD 720p videos with stereo sound.)
NOTE: &fmt=22 will not work on videos that do not fulfill the 1280 x 720 requirement.
Also, be aware that &fmt=22 will entail much longer load times, and in some cases - videos will experience audio lag. Like before, quality will ultimately be determined by bitrate and proper encoding.