Check out the video
During the show in Houston, Axl Rose of Guns N' Roses interrupted the performance of November Rain midway because the piano sounded a bit strange. During the song, Axl even asks, "What the hell was that?" , tries to continue, and then stops.
Slash's guitar goes out of tune and Axl jokes about taking the blame
“What the heck was that? Can we at least stop?! Wow, the piano is broken. So, do you have any suggestions?” The band then continues the performance, with Axl returning to the audience and laughing.
Check out the video (Axl interrupts at 4:56):
