Dension problems

[The_Laird]

I inherited a Dension iPod connector with my S8 and, because I've had one before, I'm sure something is amiss. It's supposed to play 6 playlists as if they were CDs and control is through the head unit

It will do:
1. Play music from each of the play lists (if selected via the iPod controls)
2. Advance from one track to the next from the head unit
3. Stop when the head unit is turned off or moved to the radio
4. Charge the iPod

It won't do:
1. Change from one playlist to another via the head unit controls. If you try this, it keeps playing the same playlist and then defaults back to 'CD 5'
2. Count and time the tracks properly. This seems to be a pretty random event/display.
3. Recognise one of the playlists (CDS) on the display

All I have on the iPod is the 6 playlists (I amended the 'smart' playlists) and I've tried 2 different iPods.

Any ideas?