Private voice chat bug?

I am trying to do an audio call with my friend and when it connects, I can hear her just fine, then it'll cut out and I won't hear her anymore. We're trying to troubleshoot it right now, and she is on mobile. Her voice will come back if she toggles and untoggles the speaker icon, but then it'll go right back out. She just updated the app and it still is doing the same thing. She'll talk for not even 30 seconds, and then she'll be gone.