MORE CAPITOL CHATTER: Obscured by all the talk about Gary Gersh's taking over at Capitol Records is the derby to fill the company's coveted vice president of media & artist relations post vacated by Larry Jenkins, who heads to Columbia Records in New York on July 1. Among the many names in the rumor mill are MCA's Ron Shapiro, A&M;'s Diana Baron and Hollywood Records' Kathy Acquaviva, all of whom claim the rumors are unfounded. In fact, the impending changes at the top of the Capitol tower have created an awkward lull in the interviewing process for the media post. "They'd like to get down to business and hire someone," says an industry insider. "The problem is, no one's sure who's doing the hiring."