Incoming calls not ringing the phone when using ringtones
I've seen a few threads on the subject of the phone not ringing and I too have this problem. I can be sat next to the silent phone and the first indication that someone has called is a message pops up. I have tried all the usual things mute button (it's off), volume control (max volume), do not disturb ( never used it but it's off anyway), reboot the phone, reset all settings - all done.
In my tests the one consistent problem has been changing the ringtone to one downloaded from the iTunes Store. If I do that the phone doesn't ring. If I use the default tone all's fine and i can turn the mute button on and off and the phone will then ring. If I set the ringtone to a tone from iTunes the phone doesn't ring anymore.
iphone 6 running iOS 8.4