S3 Making Water Sound

[Android Question]

Since yesterday I've noticed my Samsung Galaxy S III will randomly make water sounds. Sometimes 2 in a row. Sometimes 2 or 3 in a few hours. I'm not touching it. The screen is dark and it is facedown on the counter. It is not plugged in. Battery is nearly full. The sounds are not attacted to any notification that I can see.

I must be missing something, but I don't know what it is.

Can anyone tell me why it's making this noise?

 

[quickaudi]

It's definitely a notification. Some notifications keep going until you acknowledge them. For example, in Messaging, under Settings, there is a setting for Message Alert Repetition. Can you check if this is set to more than once?