RKO General had been under investigation by federal regulators since the 1960s for unethical conduct at its television stations, including KRTH's television sister KHJ-TV. The company was eventually ruled an unfit broadcast licensee and was compelled by the FCC to sell its broadcast properties. In January 1989, RKO sold KRTH-AM-FM to Beasley Broadcasting for $86.6 million. That October, Beasley spun off the AM station to Liberman Broadcasting for $23 million; this transaction closed in March 1990. During this period, KRTH dropped Smokin' Oldies and simulcast KRTH-FM's broad-based oldies format. Upon closing, KRTH became a full-time Spanish-language station broadcasting a regional Mexican music format branded "Radio Alegria". Liberman changed the station's call letters to KKHJ in honor of its history as KHJ. From November 1997 to January 1999, KKHJ aired a Spanish all-news format, the only one of its kind in the United States. The station's ratings suffered, prompting a return to regional Mexican as "La Ranchera".