I ran across a frustrating bug when using a GefenPro as an external DVI Matrix Router with an x20 and an M2C-50 console.
When going idle for an unknown period of time(more than 1 minute, less than 10), a bug occurs. Recalling Command keys works fine, but function keys cause the console to hang and then loses connectivity to the spyder. It then re-establishes a connection and fires all the buffered function keys sequentially.
When the console crashes it registers a Remote error in the Alert Viewer: "Telnet Socket Timed Out Waiting for Response".
Using the Gefen IV serial protocol in Spyder, I was able to get a stable connection.
To solve this issue use a serial connection from the Spyder frame to the Gefen Pro Router.
IP control can 'time out' under certain circumstances intermittently.