Since going solo from the Moldy Peaches four albums ago, Adam Green has upgraded his gleefully primitive aesthetic into a more sophisticated, knowing sound. His sense of humor, however, has stayed the same (minus a few dick jokes). But that’s the problem with his new album, Sixes & Sevens. Whenever he does something musically interesting, like using disco strings on “Twee Twee Dee,” he backtracks toward something either cutesy dumb or self-consciously weird, like the pan flute on “You Get So Lucky.” “Tropical Island” and “It’s a Fine” prove he can write eccentric songs that don’t sacrifice humor for insight, but “Grandma Shirley and Papa” and the nonsensical spoken-word piece “That Sounds Like a Pony” prove that sophomoric hijinks remain a top priority. The album’s length--20 tracks--only compounds its overriding glibness, as if Green is daring us to give him the chance he deserves.