After upgrading to 20, I noticed something very different in the behavior of MC's playback, and I am not sure when it started because I upgraded from 19 to 20 just recently and it looks like there have been numerous changes, and bug fixes since then.
So, when I am playing music from MC, no sound will play from ANY other source, like YouTube, Bandcamp, games websites or any other webpage that has sound and I know it used to. I know this because I used to listen to music, and play video games on a games website where sound is necessary. Also, lets say I wanted to pause playback for a minute or so to review a song on YouTube or Bandcamp, you can't do that without completely stopping playback, not pause, but STOP it and when you restart MC starts that song over again. Do I need to make changes in my settings to allow for this? ~Thanks~