Low Quality Video after upload: https://support.google.com/youtube/answer/71674?hl=en

Change the quality of your video: https://support.google.com/youtube/answer/91449?hl=en

Add ?rel=0&showinfo=0 to the end of the embed url.

Currently the Divi theme (Elegant Themes) doesn't support ?rel=0&showinfo=0 on the video module. The work around is to manually embed the YouTube video using the code module. Use the follow code, replacing the xxxxxxxx with your YouTube video ID.

<iframe width=“1280” height=“720” src=“https://www.youtube.com/embed/xxxxxxxx?rel=0&amp;showinfo=0” frameborder=“0” allowfullscreen></iframe>