Wow... my husband and I, too have heard squeeky toy noises: three times in our vacation home and once or twice in our main residence in Pennsylvania. This sound could not in any way be confused with a rodent sound. It's exactly like you squeezed then released a rubber duck. We have no squeeky toys in the house... getting a little freaked... any thoughts?

Heating or air release, water pipes rubbing, is there something that is belt driven? Two limbs on trees rubbing on house.

Considering it is in two locations, is it something you brought with you? Cell phone message ? Some type of electronic game?