Q: iPhone 6s rear mic not working

I just upgraded to the 6s yesterday. I recorded a video today and when I went to watch it all I heard was static. I could play old videos with no problem so it's not my speaker, and I can call someone and they can hear me so it's not the front microphone. I can also record voice memos just fine. It only happens to videos I take now; I only hear loud static, not any of the sound it's supposed to play. Has anyone else had this issue/fixed it? Should I take it to the Verizon store I got it at or the Apple Store? Thanks in advance!