BYOND Build Number: 493.1117
Operating System: WinXP SP3
Video/Graphics Card: nVidia 9800 GT
Internet Connection Type: ADSL2+ 5Mbit
Firewalls/Routers: ESET Smart Security, router: Billion BiPac 7300 G
Problem Description:
After a certain amount of inactivity whilst being connected to non-locally hosted games, the data flow between the client and the server seems to freeze. There is no immediate connection failed message, and commands seem to go through for a while but nothing seems to happen. This even occurs when connected through telnet, but on telnet the connection doesn't seem to break off unless I close it manually.
Steps to Reproduce Problem:
1. Join a BYOND game
2. Stay AFK for a while. Sometimes it takes 15 minutes, sometimes 40. It's fairly random but usually above 10 minutes.
P.S. It has recently often occured to me when I'm idle in hub:metamorphman.hangout (This is not a plug for my chat thing! :P) Other users seem to be fine.

Are you using the wireless, or Ethernet cable?
If your using the wireless, do you have the latest version of the firmware installed?
One of the reviews I found on the internet about that router explained they were suffering from unexplained drop outs before updating to 1.35 (may or may not be the latest firmware version)