The Grammys have issued an official apology to Metallica and Lady Gaga for the technical difficulties experienced during their performance of “Moth Into Flame.’ Along with the apology, a longtime Grammy producer theorized that one of the extras onstage kicked a cable, causing James Hetfield’s mic to go dead.

Metallica’s mic issue is a complicated one. Everything reportedly went well during soundcheck and a Romanian Metallica fan club reported their online feed sounded fine, with only the TV broadcast suffering. Regardless, Hetfield was livid after the performance, kicking his mic stand and bitterly throwing his guitar away once the song concluded. Drummer Lars Ulrich later told James Corden it “was not a lot of fun” being in the dressing room with Hetfield following the mishap.

"These kinds of things are horrible when they happen," Grammy producer Ken Ehrlich said in an interview with The Associated Press. "That's one of the risks of live television. My guys say that the mic cable was connected. My guys' theory was that ... one of the extras (onstage) accidentally kicked out the cable that went to the mic. Obviously, we apologize to the band.”

The Grammys also apologized to Lifetime Achievement Award winner Shirley Caesar, who was misidentified during the ceremony when a photo of gospel star CeCe Winans was shown instead of Caesar during a montage.

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