Plumage was dead on for a blue-winged warbler, but its call was consistently many buzz notes. There are at least 3 individuals present that all called the same way, much more like a golden winged.
There are also several individuals at this location that have the typical two-note blue winged buzz call. It is very odd. some of them may be hybrid individuals (bird in photo is the same bird as the spectrogram).
Brewster's