My phone doesn't make sound and thumps instead

My phone stopped making sound and now whenever sound would normally be played, something inside the phone starts loud thumping that I can feel from the lower half of my phone. It also makes the thumping even when muted but sound would normally play otherwise. It takes me muting an app in its own options to stop it, not by muting my phone, to make it stop. It also makes the thumping when I change my phones option from muted to not muted.

I won't be able to have anyone look at it until Saturday so I'm trying to find out as much as I can. Thanks in advance for the help.