My Maxx is Haunted Random Alerts While in Sleep Mode

[YellowJacket]

OK, so I have a puzzling issue. Most nights I put my Maxx in Sleep mode rather than shutting it off but every once in a while it wakes me up in the wee hours in the morning with a random alert tone. The last one was "the good the bad and the ugly" which was a text tone I had used in the past. The alert starts out normal but will then studder. If I hit the power button, the phone is still off. When I wake the phone up, there are no new texts or alerts that I missed.

David