and by association, an affiliate news service – at the time WDAF joined the network, the program – as was the case with WDAF's news department as a whole since the September 1994 switch to Fox – initially relied mainly on external video feeds from CNN Newsource for coverage of national and international news stories, although with the associated launch of Fox News Channel that August, it also added content sourced from Fox's in-house affiliate video service Fox News Edge. The Your World Tonight concept was not successful, and the 5:30 p.m. broadcast was retooled as a traditional local newscast, formatted as an extension of its lead-in 5:00 broadcast, on January 6, 1997. Not long after WDAF-TV switched to Fox, KMBC made a short resurgence in news viewership amid viewer confusion caused by the switch, overtaking it for first place among the market's local television newscasts; this situation would further intensify the ratings rivalry between the two stations. Since the late 1990s, WDAF-TV's newscasts have rotated between first and second place with either KMBC or KCTV depending on the time slot, with the station's strongest ratings being logged in the morning and at 9:00 p.m., where WDAF regularly finishes at No. 1 (in time periods where that station does not have an absolute hold in that position, WDAF competes for second place with CBS affiliate KCTV). Channel 4 has maintained its status as the ratings leader in the 9:00 p.m. hour, even as it has faced added competition in recent years from a KCTV-produced newscast on MyNetworkTV-affiliated sister station KSMO-TV (which premiered on the latter station as a WB affiliate on September 12, 2005) and a KMBC-produced newscast on that station's CW-affiliated sister KCWE (which began as a half-hour program on September 14, 2010). In February 2003, WDAF-TV launched an investigative reporting unit, the "Fox 4 Problem Solvers", which conduct investigative reports centering on businesses that have ripped off local consumers and uncovers various consumer scams. In April 2007, fellow Fox affiliate KTMJ-CA in Topeka began simulcasting the 7:00 to 9:00 a.m. block of WDAF-TV's weekday morning newscast and its nightly 9:00 p.m. newscast (ironically, the over-the-air signals of WDAF-TV and several other Kansas City area stations adequately cover most of the nearby Topeka market due to the close proximity of the two markets, Topeka being located due west of Kansas City). The simulcasts were dropped in November 2008, when