This happens almost every time a call is received or after a call is made. After a received call in the sound settings you might notice "dummy output". in most cases the phone must be rebooted. Other times you might see different settings such as default but the mic no longer responds. In that case you can log out and then log back in. The mic may work again. Saves a bit of time.
Arch Linux Phosh.
Arch Linux Phosh.