Humming/wind tunnel like noise

I got my truck last year, and when I got the truck it did not make any unnatural noises, and ran great. But, i have started to here a noise when I get up to thirty five mph, and gets louder the faster I go. Sounds like I have big off road like tires on my truck. I do however have wrangler authorities on it, bit they are not any bigger than the original stock tires that were originally on it. I have been trying to figure the problem out, but no luck yet. Can anyone help me out? It literally sounds like the humming or wind tunnel like noise that happens when you have large off road tires on. When driving on the freeway or highway, etc.