Weird noise from neighbor's backyard
Since the last 2-3 weeks, this exact sound repeats infrequently from the direction of my neighbor's yard (which is just a pool with concrete). We don't notice it once it's dark out, and are in a dense suburban area.
We thought it may be a rooster or chicken, but it sounds the exact same every time, no variation in pitch/volume. Another theory is a rusty part that's swinging, but then why don't we hear it at night (and why haven't they fixed the damn thing)?
It's annoying, but what's really driving me crazy is not knowing what it is.