I've been flying (safely) in the downtown area of Columbus, Ohio now for over a year without any real "issues." Recently, in several locations downtown upon start up...on the initial status screen that appears...I get a warning that there is "strong radio frequency interference and to not attempt long-range flights." The screen indicates that there is a poor signal for the remote. This has happened in several locations and has just appeared over the last 2 weeks...previously, tons of flights with no warnings...smooth flying and great images. I can move a half mile away from this area and the craft behaves fine and I get no warning like this. The statehouse is in the middle of downtown...state capital...I was thinking that perhaps some type of jamming signal has been initiated to keep uavs from flying close? Just fishing here. I contacted the Cols police captain, he knows nothing but is checking...I have worked with him prior to this. I know I should know this, but is the frequency between the RC and the craft adjustable? Has anyone experienced anything like this? Have I become a conspiracy theorist? Thanks for any help.