Idina Menzel's vocal chords might have been a little frozen Wednesday night ... because the singer struggled through the high notes of "Let It Go" ... and it did not go unnoticed.
Menzel performed her signature song in Times Square during "Dick Clark's New Year's Rockin' Eve."
With the temps in the 20s and Menzel all bundled up ... she clearly didn't have her usual vocal range. Fans (haters, more likely) reacted swiftly on Twitter:
So we gotta ask ...