Ringtone and Notification Sounds Change On Their Own

[Red_Alert204]

I have a Nexus 6 running Android Marshmallow, though this was happening with Lollipop too. Randomly, my default ring tone, messenger notification, or gmail notification will change, either to no tone, or just a single repeating beep. When I check the settings, the selected sound ends up being a 5 digit number. For example, my messenger tone is now 53918, no sound plays. Annoyingly for messanger, it will change the notification for all my conversations to 53918. So even if I change the default, all active conversations keep the "number sound."

This all seems random and infuriating. Any suggestions?

 

[dpham00]

Mod Note, I will move this to the n6 forums for more visibility

 

[99_9999]

bump