I found a solution to the problems I had been having with my radio (2003 non-bose radio). When tuned to certain FM stations, my radio would do one or more of 3 strange things:
- station would go silent for a second or two during the middle of songs or would pick up a different station momentarily
- radio would jump from station to station when I press a preset button, reaching the right station after going through 2 others -- or sometimes just going directly to the wrong station
- when tuned to a preset, the line below the frequency reappears (indicating that I'm not tuned to any of my presets)

I solved all of these problems by tuning to one of my presets that had the problems, and then holding down the preset button (to set the station again). For some reason, this eliminates all of the above problems.

After turning off and restarting my car I got one of the problems again (the jumping from station to station). Repeating the preset memorization solved the problem again.

I have no idea why this works, but it does for me. I was going to get my radio replaced under warranty, but I can deal with this problem if all I have to do is hold down a button for 2 seconds and it's fixed for as long as the car is on.

Hope this helps a lot of you guys out!