Gwen Stefani and No Doubt pulled off a killer performance of their hits and a new song on “Good Morning America” Friday. But sources say the earlier, 7 a.m. sound check didn’t go quite as smoothly.

PHOTOS: GWEN STEFANI

“Gwen kept forgetting lyrics to the band’s older songs ‘Underneath It All’ and ‘It’s My Life,’ ” reports a spy, adding, “She kept asking the early-rising crowd for help, and they joined in.” A grateful Stefani then told the fans, “I [bleeping] love you” and “I can’t believe you’re here so early.”