unknown musical notification???

[dr_j]

About once a week  my phone starts ringing with about a 7 note tune of unknown origin. It continues to ring for 3-5 minutes on top of any other audio I may be listening to and I can turn it off. There is no notification shown, no alarm set, no calendar appointment, but I can adjust the volume using the ring/notification vol control. How do I identify the problem?

[_alexdon_]

One suggestion would be running the phone in safe mode until this normally would happen again to exclude a 3rd party application.

[dr_j]

I have not tried Safe mode because of the unknown interval between occurences. But I discovered today that the mysterious ringing tune is actually the Sony default ringtone. I do not have this set as my usual ringtone for any phone app and the screen remained off when the ringing occured. Still a mystery.

[_alexdon_]

@dr_j by any chance you have changed some settings under accesibility?

See below:

/t5/Xperia-Z5-Z5-Compact-Z5-Premium/Power-button-plays-ringtone/m-p/1076325#M6027