I bought a couple used i-Tech 4k's. Ststem Architect would not find them. Caled Crown. They had me download HyQnet Netsetter. With it i was able to see the IP address on the ITechs. I then had to change my netbooks IP address to match the first number of characters (the last numbers have to be unique to the device). Once I had one that, reboot and retry with Syetem Architect. It now found the amps. Then you can use NetSetter to change the ip address in the amp. After that, I changed the computer's ip address back.
Obviously, I am limited in my nerworking knowledge, and my explanation is probably missing steps you'll need. Just trying to say that this is not an uncommon issue and it is fixable. Call Crown and talk to tech support. My amps are out of warranty, but the tech support guy said: "We made them, we're not going to leave you hanging". Spent over an hour on the phone. No charge and got both amps working.
(sorry about my ipad typing)