what's that sound i hear in the Z4 when the car is off?

[cruisingdownthestreet]

i tried browsing for an answer but all i found were exhaust sounds.

So I'm sitting in the car--car is off, lights are off, everything is turned off.

and i hear this "dice rolling in a plastic cup" sound every few minutes and it comes from the speedometer area, or could be from under the hood. what is that?