Bluetooth Mighty Mouse bottom shell rattle

So here's the deal,
I picked up Bluetooth Mighty Mouse yesterday. Nice package, Mouse itself looks good, everything seemed OK. Connected fine with iBook and iMac, no real notecible lags or delays, but right away I noticed some really annoying construction fault.

Mouse itself consists of two major halfs - the big top shell, and the bottom half. Thing is, that bottom half is rattling and it seems really loose, like there is a small gap between the top shell and bottom half. Feels like Apple forgot to fasten ir properly.

Anyway, a closer inspection revealed, that placing a light piece of paper between the side "squeeze" button and outer plastic shell stops the rattle, as the bottom half is pressed firmly together and without a gap.

I made a quick sketch to illustrate the problem.

So what do you guys think about this?
Should I take it back? Somehow I don't feel like they will exchange it, because it's not really "broken" by Apple standarts.