Blaupunkt DX-R70 Satnav unit.

[stevekyd]

This unit works perfectly with the 2005 DX map disc which I've been using for a few years now. The unit will not accept a later DX disc- 2005/6 or 2007/8, all discs work perfectly in the DX-R52 unit fitted in my other vehicle. When I try to use the later discs in the DX-R70 the message -NAVI WILL BE ACTIVATED - shows for approx. ten seconds followed by the message -NO DX MAP DISC INSERTED. Can anyone give a reason/cure please. Thanks Dave.