I had that problem once before: I would log on and about 1/2hr into playing my character got the "red dot of doom" to appear and i d'ced and COULD log back in, after i reset modem and computer, but would happen again faster. Had the Comcast people out here and on the telephone poles and checking everything. Final discovery: birds or squirrels had been using the wire from my house to the pole so much that their nails and claws had punctured the wire and then any amount of air or moisture compromised the signal being received after wire heated up enough to open the claw rips/punctures on the wire. They replaced the wire from my house to the pole; added some sort of thing to the coating to deter them from walking along it; problem hasn't happened since. See if that might be it?