What changed? Did you add any lights, replace any lights?
If nothing has changed but the interference had just started recently, I would be looking for a ballast going out (try replacing the tubes first), or a CFB that may need replacing, or possibly even a LED bulb that lost a capacitor.
Try unscrewing a bulb at a time until the interference disappears.
If you have a dimmer switch that is normally kept turned on full, double-check that the dimmer switch is indeed set on full; the dimmer on my chandelier generates a lot of RF interference except when all the way on or is completely off.
Water in the wiring could also cause problems, so don't rule out the possibility that you might unscrew all the bulbs and still have interference.
My very humble setup:
|Man Cave:||Vizio E500i-A1 "Smart TV" (50-in 1080p 120Hz LED/LCD, has Netflix app.), Blu-ray players (Sony BDP-S3100, old LG BD390), Roku (the original model: N1000), PC (Windows 7), Comcast Internet (25Mbps/5Mbps).|
|Bedroom:||LG 32LV3400-UA TV (32-in 768p 60Hz LED/LCD), HD DVR (Motorola RNG200N), Xfinity Comcast cable (Digital Starter Package), DVD/VHS player.|
I've heard of compact fluorescent bulbs and LEDs producing RF interference, although they are supposed to be designed to minimize that.
This may just be a 1950's-era urban legend, but I ran across a web site that was talking about tungsten filament incandescent light bulbs causing RF interference with 1950's television reception. The story alleged that when the tungsten bulbs containing inert gas were initially commercially popularized and put into residential use in the 1930's, the filament was configured in a way that produced RF waves, but at frequencies that did not cause any interference with AM radio, so people did not notice any problem. Over the course of twenty or so years, a different filament configuration was introduced, so by the time TV got going in the late 40's and early 50's, most of the problematic bulbs were gone. But some of the unruly bulbs remained on the market and persisted (in porch lights and other fixtures) into the TV age and caused some problems with TV reception.