when i switch from ipod to, let say, HD radio, it seems the ipod will keep playing the songs. because when i switch back to ipod, it moved on the later songs. i never had this problem with my old Z1/Z3 map. is it the ipod issue or z110bt issue?

now it's funny you should say this but i think mine may be doing the same, i thought i had pressed the shuffle as the song was different from when i last played it and it was halfway through - will have to investigate further

I tested this today and mine pauses the ipod when I change sources.

i think this may be an intermittent fault on mine

Try restoring your ipod and re-syncing your data.