Radio Stations Change on Their Own

I have only witnessed this occurrence on a single occasion. I don't drive the CX-5 too terribly often.
However, my wife insists it happens continuously (her DD), and that she no longer listens to the radio, because it constantly just changes w/o being commanded with the knob/rocker switch.
I keep asking her if she is certain it could be reproduced in the 5 or so minutes a Mazda tech might take it for a spin. She insists it could, because it occurs so frequently. This seems like one of those things that could take forever to be diagnosed without a TSB.

Has anybody else suffered this issue? I could imagine it being pretty aggravating.
I've got this, and a few other issues I need scoped out, on my next service visit.

Maybe she is hitting the 'next' button on the steering wheel without realizing it?

I kept suggesting that, believe me. LOL!
Every time I did, she got insulted and angry. haha!

The one time it DID happen when I was driving, I am certain I didn't inadvertently actuate a button. I know that much. So, there is bound to be some merit to what she is saying.

This happens in my 2013 CX-9 when listening to Sirius, although not frequently enough that it's really a bother. Maybe once/month? I never listen to regular radio so I can't speak to that.

Scan button perhaps?