Real Housewives of Orange County star Vicki Gunvalson’s recent ex-husband (as of 2010) was caught frequenting sex clubs!

A source is revealing that Donn Gunvalson has been spotted at Freedom Acres swingers club in Devore, California.

“I recognized him immediately, and once I started talking to him he introduced himself as Donn,” reveals the source.

“He went to the back room with the woman he brought and they were engaged in public sex.”

Say what!?!

Here’s the thing Freedom Acres is the largest swingers club in the Los Angeles and Orange County area and you need a yearly membership to enter, so clearly this wasn’t a one-time thing.

“I’ve never seen him have sex with anyone other than who he brings,” the source adds.

“He just seems to really enjoy public sex and the vibe of the club.”

Vicki has moved on and is dating a new man, but she has yet to comment on Donn’s recent activity.