Baby pac chirping?

[pansie]

could it have been his/her feet squeaking on the glass?

[GrifTheGreat]

could it have been his/her feet squeaking on the glass?

This is also a possibility. Even though I have heard baby Pacs make little peeping sounds this could very well have been what you heard unless your frog was out and about. Pacs are usually quiet unless a male calls or either male or female become angry.

Grunting is kind of common among adult females. Both male and female can make this popping clicking sound as well. Sort of like talking, but of course nowhere near the same. Both of mine made noises as babies that was a chirp or peep, but very rarely. Both only made these sounds a couple times. Most of them make no sounds at all as babies. It is possible you heard your Pac make this sound, but unlikely due to the sound not being very loud so it probably would not have been audable through the glass of your frogs tank.