Download the program http://www.wireshark.org/
and use it on your network card. If you get disconnected, you'll see the packet information, it should give you more details on your problem. Be warned, this program will give you information on packets, networks so you gotta have a good background on networking...but taht wont stop you from saving the info it grabs and sending it here.
in other words, if a packet is responsible for your disconnection, you or someone here will probably see it.