This has been happening for a while.When someone leaves or joins the session, FS freezes for about 3 seconds and starts again. This has become very annoying, and somewhat dangerous on approach. Anyone got an idea how to fix this?

Brendan, change your interface to use connect VATSIM first. If you use SB3 , changed to FSinn or reverse.If not fixes your problem, possible problem reasons are;-antivirus program protection; generally nod32 is creating this problem.As far as I know there should be a settings about exception some programs inside of NOD32.(I can't remember section of this settings, it may be AMON or like thats)-firewall settings; check your exceptions in your firewall list, you have to get sb3 or fsinnin exception list-check modem protection; evenbe you set on windows firewall, some of modem's itsown firewall protection system obstructs to connection from outside. You may open ports for to use of SB3/fsinn once again in modem settings.

This has been happening for a while.When someone leaves or joins the session, FS freezes for about 3 seconds and starts again. This has become very annoying, and somewhat dangerous on approach. Anyone got an idea how to fix this?

If you are using SB4 and FS9 try to disable UPnP on your router settings. I had the same problem and just resolved it this way.John