Can't hear other person when I receive a call

[UndeadSquirrel]

I just got this phone yesterday and I'm already having issues. For some reason when someone calls and I answer, I can't hear them, and the "Speaker" option is grayed out, but hold and mute are still usable. I've rebooted the phone and I'm about to try a hard reset, but this is just ridiculous. Anyone else had this problem?

In fact, I don't get any sounds at all, except notifications and ringers. Apps and games have no sound at all.