Do any of you have the Firfox 2 RC3 installed? I installed it a little while ago and my AS 3.8 would hold a connection but then it would just drop at a consistent time (couldn't tell how long, maybe 5-10 minutes). I uninstalled FF2 RC3 and it work like a charm.
I don't know if any of this is related but I thought I might pass it along if it has the potential to help any of you.
Other 3rd party software installs might be something to consider.