There was that time I was tripping on acid at 2am and was offended by hearing the same Doobie Brothers song that plays during my drive in and my drive out and called up the college radio station thinking, "I'm either going to talk to the janitor or the program manager", turns out the program manager picks up the phone and I ask him, "Who picks this music out?" and he says "I do" and that it's programmed on the computer. I told him "Come on, you can play anything you want to play" so he put on a Miles Davis disc.
Your Miles Davis comment triggered a memory of college radio. In school in the early 90's, I had a 3-6am show Wednesday mornings, and mostly said and played whatever I wanted, as nobody was really listening anyway. One week, the guy who did the Friday night 6-8pm slot called me and asked if I could sub for him. I was way down on the call list, but nobody wanted to sub on a Friday night. So I took his slot and did my normal show. I immediately got a bunch of complaint calls that I was crap (which was fair, I was), and one guy who kept calling in over and over demanding I play Miles Davis.
On the other side of the coin, I also had a 10am Saturday news slot, which was just a quick 10 minute read of my pick of the top stories off the AP feed. I was on the city bus discussing the slot with my buddy who did the sports right after me, and the bus driver overheard us and said he listened to the station on his bus route, and loved us on Saturday mornings more than the other news readers. He was my only known fan in my very short lived radio "career".
I did college radio for a bit. You could play whatever you wanted up to a certain extent. At least where I was at, ~'06, you could play like 30? minutes of whatever you wanted, it's been a while might be more or less. The other x minutes of your hour you had to play a selection of music. It was a very wide range of things so you could easily find something to fit into your show but it had to be from the pool that college got.
Maybe other colleges did it differently but we didn't have a program manager or anything. Everyone was free to do what they wanted outside of some FCC rules and what I previously mentioned.
One time I tuned into college radio and not long after came on a song from my own band. The only recording of our music was from a jam session that we put on CD that we handed out to a few friends and we hadn't played together in many years by that point so it was quite a shock to hear it.