First, try troubleshooting just a single deck to see if that will connect and communicate. If it can, then there's no issue with your computer and the problem is the switch/hub you're using (or possibly some of the cabling).
More often than not, however, the problem is the computer, as there are a few places it can choke the connection - including, but not limited to, an ethernet adapter, having WiFi enabled, the firewall, the ethernet zone setting (Windows - Private vs. Public), having other servers or network services running, malware / viruses...
Start with this article for some basic troubleshooting steps.