Internet connection breaks down during downloading

Hello

During downloading of any application from the creative cload ALWAYS my internect connection fails.

I cannot dowload more than about 10 % of the application. Then it stops and I have to restart both my Imac and modem to reestabish the internet connection.

I switched off all firewalls (both in Imac and Cisco Linksys E4200) but the problem persists.

Can anybody help?

Kind regards 

Lex