Audi seems to be suffering from declining loyalty — or rather, the spouses of Audi owners may be. Married people who drive an Audi are the industry’s biggest adulterers, according to a British Web site that helps them do it.

The site, IllicitEncounters.com, which proudly describes itself as “the UK’s leading married dating site,” says Audi displaced BMW as the most popular auto brand among its 800,000 members. It says 22 percent of its members drive Audis and 14 percent drive BMWs.

German brands nearly swept the top five, with Mercedes-Benz ranking third and Volkswagen taking fifth. Volvo was fourth.

“All the cars in the top five represent our members — they are typically successful, motivated, high achievers who are less likely to settle for something they find unsatisfying, be it a car or a relationship,” spokesman Mike Taylor wrote on the IllicitEncounters Web site.

On the other hand, those whose spouses drive a Hyundai may be able to rest easier knowing that fewer than 2 percent of IllicitEncounters members drive one. The only brands less popular among cheaters are Peugeot, Renault, Rover and Skoda, none of which are sold in the United States.