Two DJs claim their drinks may have been spiked to impede their performance on stage.
Optimus Gryme said he was drugged before performing at Hawke's Bay festival Valley Vibes on Saturday. He swore at the crowd when a group of people booed Tiki Taane for stopping because of a technical problem.
He told the crowd they had no idea what it was like being a professional musician.
Taane and other musicians had to step in to calm him. Taane then took over the microphone and continued with the show.
Concert-goer Erin Nicholson said Gryme's "obvious intoxication and foul language made for a poor mix".
"We were shocked, it was awkward and very unprofessional."
Gryme apologised on Facebook for acting like a "complete twat" but believed his drink was spiked.
He said he had three or four vodkas, took no drugs and was "completely fine and coherent" at 6.30pm, but "blacked out" by 8pm.
"I apparently spent over two hours running around doing crazy out-of-character s..., none of which I remember," he wrote.
He wanted to hear from people in Hawke's Bay who might shed light on how his drink got spiked.
"This sort of stuff is not on and needs to stop. I have a wife and two young kids to look after."
DJ Harry Organikismness wrote that he had had his drinks spiked four times.
"It makes me think that some of these spikings are not ‘date rape'-type spikings, they're more people trying to make a fool out of you."
Valley Vibes organiser Greg Miller said Gryme "lost his cool a little bit but he sorted it out" and people still had a good time.
Neither Gryme nor his manager responded to requests for interviews.
- The Dominion Post