Rhythmbox could not initialise the Ipod so I used Gtkpod and used Rhythmbox to copy songs into the Ipod.
Can access these files with Nautilus and can play them with Rhythmbox.
The Ipod will not play them and says "use Itunes" if pressed.
Looks like the Ipod uses some sort of song-index which is not working.
Moving files from and to the Ipod (drage and drop) makes Rhythmbox and Gtkpod crash.