Restarting your game/PC does nothing. The biggest root of the problem is how Windows operates with default settings. When cross-play became enabled, some of the game's sound settings changed, too, which required almost every PC player to properly set the Sound settings on the computer itself, NOT the game. For any PC, the motherboard is set as the audio default for Recording and Playback. Later, when you add USB speakers, Mics and/or headphones, they are automatically set as default so that sound can come out of them. HOWEVER, Windows does NOT remove the motherboard from being default. The result is that when you check your Sound and Recording Settings, you'll see that there are multiple items set as Default (signified by a green check mark). What you want to do is select your speakers OR headphones and click the SET AS DEFAULT button under the menu, and it will remove the default status from all other items. Do the same thing in the Recordings tab, and that will fix the sound and mic issue with D2.