The station is owned by Audacy, Inc., and airs an adult hits radio format known as "104.1 Jack FM."

Partly due to signal limitations and impatient management, the 104.1 FM frequency went through many format changes throughout its history.

Both stations moved from their studios in St. Louis Park to new facilities in Eden Prairie (which today is still home to 950 AM).

[3] The FM station broadcast in stereo for the first time and moved to an album rock/Top 40 hybrid format, soon changing its call letters to KFMX.

[6] It was up against established country stations in the Twin Cities, market leader WDGY, low-rated KTCR-AM-FM and soon, KEEY.

"[7] KJJO's ratings improved with the classic hits format, but the station was still not making much of an impact in the market.

In February 1987, KJJO transformed yet again and introduced a hard rock format, to go head-to-head with the classic rock-leaning KQRS-FM.

Over time, KJ104 garnered positive word of mouth in the Twin Cities area, though ratings were still mediocre.

In the summer of 1992, KJJO announced it would switch back to country music, which was increasing in popularity, amid a large outcry from KJ104's dedicated modern rock fans.

[10][11] At 6 a.m. on September 8, after signing off the modern rock format by playing "It's the End of the World as We Know It (And I Feel Fine)" by R.E.M., "Thunder 104" debuted.

[13] Also that same month, several former KJ104 employees were working at bringing the rock format back to the local airwaves, which culminated with the debut of REV 105.

Two months prior to this, hard rocker KRXX became KEGE "The Edge," and was soon the highest-rated modern rock station in the country, succeeding where KJJO, as KJ104, failed.

[17][18] After gradually adding in songs from the 1980s throughout the course of 2000, WXPT shifted to a full-fledged '80s hits format on November 17, 2000, and rebranded as "Mix 104.1."