Rape is no laughing matter to Margaret Cho or to the audience that walked out of one of her performances on Saturday night.

Cho, 47, performed at the Stress Factory comedy club in New Brunswick, NJ, on Saturday to a sold-out crowd, but not a happy one. Witnesses tell Page Six that Cho opened her set by talking about Garry Shandling’s death and her own rape instead of telling jokes.

“She kept on talking about rape and how bad rape is, and it evidently pissed off a few people in the audience,” an audience member told us. “She really got into it with the hecklers. It turned ugly and it just got brutal. People were walking out like crazy.”

An insider at the Stress Factory says Cho’s bizarre behavior was unexpected as the comic was “fine all weekend.”

“I don’t know what happened in between shows Saturday night, but she was so out of it that she couldn’t even walk to the stage for the 9:45 show. She needed to be helped [up] by her boyfriend. Then she started her set, and every other word was ‘like’ and ‘umm,’ and it seemed like she was trying to remember her act as she went along,” the insider added.

“A lot of what she was saying was her actual standup material, but she kept forgetting the punchlines, so she just repeated [herself] over and over again. It took about 10 minutes until the audience really started to chatter, and no one heckled her at first. Then when she started to tell the same story for the third time in 15 minutes (maybe even less), people had enough and started to leave. The setup to the joke she was trying to tell was ‘rape is bad, kill your rapist.’ It sounded to an unknowing audience that she was just chanting that rape is bad, and then she started screaming ‘kill your rapist’ over and over again.”

A different source claims that Cho couldn’t comprehend that her jokes weren’t landing, especially after getting standing ovations for her three previous sold-out performances that weekend.

“She started asking the people what was wrong,” the source said.

TMZ obtained a video of Cho telling audience members as they exited, “You will never get a cent of the money back that you paid.”

Cho was wrong about that part, according to the source, who said, “[The club was] giving a lot of refunds.” Another attendee told us that the Stress Factory staff issued free tickets for another show of the recipients’ choice.

But Cho’s ranting behavior continued long after the camera stopped rolling.

“She kept going even though the entire audience was either walking out the door or talking amongst themselves, and she kept asking why people were talking. When she noticed a guy in the front row with his back to her, she started yelling about white privilege and said the audience was victim-blaming because she was trying to inform us about rape,” another witness said. “Then she said that Trump will win the election because of everyone’s white privilege. By that time, most of the crowd had left and were hanging out outside, and the people who were left started screaming back and forth, and a scuffle broke out.”

Another source who witnessed the meltdown tells us, “She walked two-thirds of the audience, and they generally weren’t even angry, just concerned for her safety. [Cho] was so incoherent onstage that a table of doctors at the show said they stayed despite the poor performance for fear that she would need medical attention.”

After the show, Cho tweeted about the incident, insisting jet lag was to blame. She also encouraged rape survivors to speak out about abuse.

Stress Factory owner Vinnie Brand released a statement on Monday about Saturday’s debacle.

“We will encourage our friend Margaret [Cho],” Brand said. “We will help her get on with the process. We will applaud her and support her and we will let her know what so many other artists know, the Stress Factory loves you. We know the struggle first hand and we are there for you too. We know that the comics are also one of the most important aspects of our business…I want you to forgive us and let us make it up to you. I also want you to consider this when judging Margaret. She tried something extraordinary. She bared a truth too difficult for too many people to even talk about privately.”

Cho’s team followed up with a release of their own.