Kobo Libra 2 rear panel loose... normal?

Purchased reader last month, and after a few
weeks use I've noticed the rear casing is slightly
loose, that is it moves in and out of the front
casing, with very light finger pressure. It's on
the long side opposite the buttons.

There's also a very light "squeaking/clicking"
sound as this happens, and you can actually
see it moving with the naked eye.

Do I have a defective unit, or is this sort of poor
quality control typical with Kobo readers?

Thanks in advance for any thoughts. :)