The station is owned and operated by iHeartMedia (formerly Clear Channel Communications) and broadcasts a classic rock music format on its primary HD radio, while its HD2 channel carries an oldies format that is simulcast to analog translator station W265CV (100.9 FM).

The nickname “Radio Free Madison” or “RFM” was coined to distinguish the evening programming from the daytime content.

The station's HD2 sidechannel launched in the mid-2000s and originally aired an all-comedy format, until converting to a commercial-free alternative rock format in 2007, chiefly employing announcers and alt-rock playlists from Clear Channel's national format lab but employing the former "Mad Radio" branding that previously used on two other Clear Channel Madison stations (at 92.1 FM and 96.3 FM).

After iHeartRadio dropped Socially Sound in Summer 2014, 101.5-HD2 would feature a rotation of various iHeartRadio channels, among them "Roots of Rock" (1960s/1970s progressive/album rock), "My 80s" (80s pop songs), and "re-Covered Radio" (modern cover versions of iconic songs).

[3] In November 2016, WIBA-FM-HD2 would convert to a simulcast of all-sports sister station WTSO (1070 AM), which already had a presence on FM since 2014 at 100.9 MHz (W265CV).