How can I fix my Blaupunkt cd30?

I have a Blaupunkt cd30 in a vauxhall combo van. A few weeks ago I pulled the unit out to wire some rear speakers in, replaced, but accidently damaged the antenna cable, causing poor reception.
I got round to pulling the unit out again today and repaired the antenna. However, on replacing the unit, I found that none of the buttons operate, including on/off and volume. The unit does come on, does a search, and stays on the first station it finds, so i am left with one radio station at the same volume. I 've tried disconnecting the unit and reconnecting, no change. Also tried pressing and holding AS and ON together, and pressing and holding all buttons separately.
I'm stumped, any help?

rgh
May 2011