DAVE MATTHEWS BAND - Even before their multi-platinum debut, this Charlottesville quintet - imagine Peter Gabriel crossed with Hootie and the Blowfish - had become the pride of our nation's undergraduates. Now, as the band's new release, "Crash," dodges the sophomore jinx, the kids don't seem to mind that their humble heroes have become full-fledged rock stars. They still pack every show, sing along with every song, and purchase Dave screen savers for their laptops. And, like the band they worship, they still ignore everything the Alternative Nation says is cool. With Ben Harper, who interprets soul for the Birkenstock set. (Jones Beach Theatre, June 9 at 8.)