The station's original call letters were KGRA and it broadcast under the moniker of "NOVA 104" from 1976 to 1981. Nova 104 played a format of AOR (Album Oriented Rock) music with laid back air personalities who each programmed the music for their individual shows from one of the largest vinyl album libraries in Louisiana. The format featured everything from AC/DC to Frank Zappa and included progressive country such as Jerry Jeff Walker and Rusty Wier. Nova 104 also featured a weekend Jazz show which added to their diversity and appeal. The station offered a "hip" alternative to the news that complimented the AOR format by running nationally produced entertaining news bites called News Blimps and locally produced tidbits called Nova Information. The station was also community oriented putting on several concerts over the course of its history to raise money for worthwhile causes including the "Save The Arcade" campaign. Then in 1981 the station switched its format to Top 40 and its call sign to KBIU. In 1986 the format was flipped to CHR (Contemporary Hit Radio) and the moniker changed to "Bayou 104". In 2005, the station switched from broadcasting at 103.7 FM to 103.3 FM. It had most recently continued the format although the moniker became "B103 The B". The station was flipped to a Variety Hits format under the Jack FM branding in May 2008.
The station was originally located physically on the 6th floor of The Pioneer Building in downtown Lake Charles which is now Lake Charles' City Hall. The station's original frequency was 103.7 and broadcast at 100,000 watts from a 150 meter tower originally allowing for a great area coverage allowing it to also cover the Beaumont, Texas area.
The station was downgraded in power, height, and frequency from 103.7 to 103.3 in 2005 by its current owner Cumulus Media in an attempt to allow for KHJK to be re-aligned as a Houston,Texasrimshot station.
On March 23, 2012 KBIU changed their format to adult contemporary, branded as "Warm 103.3" using Westwood One's Adult Contemporary format.