This is just a little video of hummingbirds at (or around) the feeders hanging by our patio.
The occasional squeaking you hear is coming from the hummingbirds (but not necessarily the one in the frame).
From what I've read, the ruby-throated hummingbirds with white throats are either female or juvenile males. The juvenile males begin to show greyish streaks-- or even the occasional ruby feather, here and there-- on their throats, late in their first summer (or early fall). By the time they come back north, most of them should have the full throat of iridescent, ruby feathers.
The ones we've been seeing are mostly juvenile males, I think, with maybe one or two females in the mix. I've read that the adult males migrate first, followed by the females and juveniles, so that explains why I haven't seen a really ruby-throated bird lately.