What’s the deal with Randy Quaid? The 65-year-old actor best known for his role in the Farrelly brothers’ underrated bowling comedy “Kingpin’’ and his dramatic turn in “Brokeback Mountain,’’ continues to behave bizarrely. A few years ago, you’ll recall, Quaid and his wife, Evi, sought asylum in Canada, claiming that “Hollywood star whackers’’ were out to kill them. (The couple stayed for a while but were later arrested as they attempted to cross from Quebec into Vermont.) Last week, Quaid tweeted a picture of himself at Tanglewood, the summer home of the Boston Symphony Orchestra, with the caption: “Rehearsing for my StarWhackers concert to benefit Barry Diller’s ‘Find a Cure for Crabs’ fund-raiser. #soldout.’’ A BSO rep said there is no such concert planned.