Bad news I'm afraid
Licencing restrictions require that Magic's myPlayer is only available to UK based listeners. Magic uses a system to determine your geographic location via your IP address to make the decision.
Multi-national corporations and internet service providers sometimes have their network configured in such a way that it makes it appear to the Magic's myPlayer that you are trying to listen from another country.
If you are in the UK, please ask your IT department if you're able to use a UK based proxy for internet access.
Check out magic.co.uk