KCBX first signed on July 27, 1975 and began airing a variety of NPR programming, plus jazz, classical music, and foreign-language shows.
[5] In parts of the Santa Barbara area, sometimes during atmospheric ducting, co-channel KPBS-FM in San Diego can override or interfere with the KSBX signal.
As part of the application, the station enclosed copies of numerous letters and emails from listeners complaining about the signal override or interference from KPBS.
In support of the frequency change, a consulting broadcast engineer was hired to analyze the situation, make signal strength measurements during ducting, and fully explain the technical causes of the problem to the FCC.
KCBX announced on December 20, 2022, that it would close down KSBX by the end of the year, stating that climate change had increased the ducting and its related interference.