Tim Mays wants to set the record straight. The kingpin of the Casbah, the San Diego club credited with spearheading the city's much-hyped four-year-old music scene, is sick of the press' obsession with (1) Eddie Vedder's growing up in San Diego and (2) the hard-rock buzz band Stone Temple Pilots' supposed roots in the San Diego scene. ''Vedder packed up years ago and has nothing to do with what's going on now,'' says Mays, and the Pilots are ''from L.A. Period.'' There is plenty of talent worth hyping, however, which explains why the place is crawling with music-biz types hungry for the Next Big Scene (read: Seattle). Rocket From the Crypt and Drive Like Jehu have signed with Interscope Records, and many other bands have either signed or are negotiating deals. But more important than the talent, says Mays, is that the estimated 300 San Diego bands really like one another. ''Bands actually go see each other's shows,'' he says. A nice plus, but in the end it all comes down to chops. ''What's happening here isn't very different from what's happening everywhere else,'' says John Reis, singer/guitarist for both Rocket and Jehu, ''except here the bands are 10 times better.''