I have a Samsung Mini 2 and my wife has an original Samsung 2. I am working with Rhythmbox on 12.10.
I was initially able to sync my Mini with RB when I first set up. Then I deleted all the music that I had synced...but now, it will no longer sync with RB. RB can see it and can poll it and tell how much space there is etc....but the sync button is grayed out.
I originally thought that I must have deleted a special file when I deleted the first set of music. However, when testing with my wife's phone, the same problem exists. I can drag and drop from various folders on my pc on to the phone...but it just won't sync via RB. I tried the empty file .is_audio_player but that had no effect.