The station's influence and popularity waned with the waxing of FM radio in the late 1970s—by the end of the 1970s, however, as rock music continued its shift from AM to FM, WTRU had shifted to a full-service adult contemporary format.
As FM radio gained popularity in the late 1970s, the station's influence began to decline. However, by the end of the decade, it had adapted to the changing musical landscape, transitioning to a full-service adult contemporary format that would appeal to a broader audience.