voice chat unavailable

In a lot of my games vc is unavailable and my teammates have an x next to their mic and ik im not vc banned coz i was never notified and it isnt every game. Like it can happen 1 game and then i can hear everyone and talk the next. Also when it happens team chat is fine, its only the randoms we're playing with. This used to happen every once in a while but recently its happening like every 3 games, Ive checked my vc settings when it happens and there's nothing wrong with my stuff. Everyone else in the lobby can hear each other when it happens for me too. is there any solution?