Occasional Rattle - Dealer for Service or No?

I have a KC SE with RF sound. There is a rattle coming from the dash that isn't horrible, but I absolutely hate rattles. The rattle isn't always there, which drives me even more nuts. It tends to do it at highway speeds over concrete roads that a bumpy due to expansion joints most often. It sounds like it's coming from dead center of the dash, around the center speaker. Of course, rattles often sound like they're coming from somewhere other than where they are...

I have to take my Titan in to have the passenger seatbelt looked at anyway. It locks WAY too easily and drives my girlfriend nuts. I want them to fix my rattle, but I know from personal experience what a PITA it is to find a rattle, especially ones that are occasional, and they'll probably just say they can't reproduce the noise. Any opinions? Has anyone else had the rattle and had it successfully stopped?

Oh, and my dash sqeaks occasionally, too. Apparently the plastic around the gauge cluster isn't seated perfectly. I'm definitely mentioning that to the dealer. I read someone else on here heard the same squeak, smacked the dash twice, and hasn't heard it again. I can temporarily stop the squeak by pushing on the plastic surround, too, but it comes back...