Looks like it's a bug! Try either restarting chapter 2 or reinstalling the game
Oh, now I see!.. A MacBook is actually the only device I wasn't able to test for bugs because I don't have one. Unfortunately, there's nothing I can do about it right now. I'll try to contact a friend who has a MacBook later and see if I can figure out what's causing the issue.
By the way, have you tried chapter 3? Is Vir the only character whose voice doesn't work there as well?