I have a factory radio on my 1997 F250 and work only a couple days a week for no reason. One morning it will work all day, and the next moring it won't work, and perhaps 3 days later it will again. At nite when I part it, and shut the truck off, I suspect it won't work again, but when I trun the key on it will work, and several times after that, putting yhe key on, it'il work. The next morning wehn I start it , the radio won't wirk tge ntire day. The radio lite that lights up the buttons work, but the radio doesn't work, nor light up the radio stations to indicate when tge radio is working. Why such a strange on again off again thing. It has a mind of its own. I check the fuse and it's not blown. The radio is just sporatic. Anybody have an opinion?