Could Mariah Carey’s famed multi-octave range be less than it was a few years ago? The musical icon’s team wasn’t commenting Thursday, but after Carey’s “All I Want for Christmas Is You” solo — sung for the big “Christmas in Rockefeller Center” broadcast on NBC Wednesday — was isolated from the TV performance’s background accompaniment, people are wondering.

First of all, the diva showed up hours late for a Tuesday taping, forcing the network to pull the plug on her pre-recording her number. Instead, Carey sang live — appearing to struggle through the song and have difficulty with her in-ear monitors. The singer looked unhappy throughout the entire performance.

Check out Carey’s performance here.

• This is not the first time issues about Carey’s vocal range have surfaced. Earlier this year, she was faulted for her singing during an Australian concert tour.