My phone doesn't ring on incoming calls. I don't know that it ever has, as I receive so few calls.

The call is announced on screen and vibrate works, but the ringer doesn't sound.

I've checked that it's enabled, the volume is turned up and "Do Not Disturb" isn't enabled.

When I select a different ring tone the selected sample plays OK so the ringer itself works.

Is there something else I have overlooked?