Get the Smartenna or disconnect the motor entirely.
I don't have the CD player, so I just disconnected mine entirely (incredibly simple to do). I do listen to the radio, and even with a lot of hills and trees between me and the distant transmitters, my reception didn't suffer when I disconnected it. There are a couple of spotty places but not bad. The antenna is still connected, as far as I know, it's just not extended.
It'd be nice if I could mount a switch somewhere to manually raise it, but even without that option, I prefer it down.