Nyle DiMarco, past winner of Dancing with the Stars and America's Next Top Model and deaf advocate, is unhappy with Jamie Foxx for a Tonight Show promo in which the Beat Shazam host does fake sign language.

"It is straight up disrespectful to make up sign language," DiMarco tweeted at Foxx. "Everything is in gibberish."

"How is this allowed?" he tweeted at the Tonight Show and host Jimmy Fallon.

He expanded on his initial displeasure in a follow-up post, explaining that sign language is the "bedrock of deaf culture" and only 2 percent of the world's 70 million deaf people have access to sign language education. It seems like DiMarco is mixing up two numbers -- the World Federation of the Deaf says that 80 percent of deaf people don't have access to sign language education, while only 2 percent of deaf people receive sign language education. Either way, that's a distressingly low number, and not something that should be taken lightly.

"We simply do not make fun at the expense of other cultures, especially those with a history of being marginalized. When we do this, progress takes a step backward," DiMarco wrote. "What Foxx did on Fallon Tonight made our struggle that much harder."

Foxx has not responded, though NBC reportedly reached out to DiMarco.