I have a 2016 Camry and while driving intermently the chimes go off. A simple bong bong and may happen again that day or maybe not happen for 3 or 4 days.

Since your car is under warranty I would take it back to the dealer for repairs.

When she ..bong bongs....are there any warning lights on or flashing?

No warning lights,no courtesy lights blinking on and off. Checked tire pressure even though warning light was off. It could happen a few times a day or not happen for a couple of weeks. I realize that in order to locate the problem it needs to be heard. Dealer just says I have no idea. I'm thinking if it's happening to my Camry it's probably happening to others so by some off chance I just thought I would ask.

Make sure the dealer documents your issue so you will have backup when you make a warranty claim.

This sounds like a faulty seat belt buckle switch. Are you sure the seat belt warning light is not on when she is bonging?

I have not seen it on or flashing on or off but I will pay closer attention. Thanks for the suggestion if I find out this is the problem I will get back to you.