I'm trying to set up an Airport network, and having severe problems. First I tried to set it up manually, putting in my wireless ISP's static IP address and DNS gateway. Then I ran across something I didn't know, the "router address". So I set it to set itself up automatically. I'd plugged in the sound cable from my Apple speakers, the printer USB cable and the Ethernet cable of my ISP's connection box (which describes itself on its cover as a "switching adaptor"). I got a message to say the Airport network (which gave itself the name Apple and a bunch of letters and numbers) had been successfully set up. So I tried to play a tune from iTunes on the speakers. iTunes played the tune, but not on the speakers. Then I tried to connect to the internet, and got an error message from my mailer and my browser. The Airport Express light was flashing orange when I looked. What am I doing wrong, and how do I correct it?