oh my goodness! haha i thought i was OCD for noticing (and correcting)) this problem. the click is actually coming from the backplate under the space bar as there is a little space for movement there underneith.. so when youre holding the phone and press down in that area you will hear a click.
simple fix was to place a small peice of electrical tape along the side of the battery and edge of the phone underneith the backplate. place it exactly where you feel the click.
hope this helps! dont forget to thank me if it did
if this is a little unclear let me know and i can post a pic.