Faulty disc or superceded?

Just bought my first Audi (54 plate A4 sport). The sat nav reads the Eastern Europe disc fine but not the useful disc 1. These are 2007 RNSE discs. The message reads "cannot read DVD, please check the disc". I bought another 2007 one thinking the disc was just playing up but get the same message. A 2008 version i bought second hand does the same.

My knowledge is very limited but could the guy i bought the car from tried a 2009 version and made the older versions defunct? I can't get in touch to ask him. At the moment i can get to effing Slovenia no trouble but not anywhere useful. Want to avoid spending 150 knicker on 2009 disc if it's going to do the same.

Can anyone help?

The laser must be ok as it reads the eastern Europe disc and cd's ok. I've tried 2 different 2007's and a 2008 so also unlikely all 3 discs are shoddy.

Scratching my head.

Not sure what all the abreviations mean but thanks for your input. Like i say i'm a complete novice when it comes to this stuff.