refrigerator: compressor noise

[George]

A couple of months ago, we bought a Whirlpool top-freezer 'fridge.
Recently, it's developed a vibration noise, when the compressor is
running. It's not OMG-loud or anything, but it's quite noticeable,
enough to easily hear in other rooms.

I can stop the noise, by pressing (not very hard) on the compressor, or
even on its mounts. The mounting bolts aren't loose. The compressor
doesn't feel particularly hot.

Is this something to worry about? Is there a simple fix for it?

Thanks,
George