I change my passwords on a regular basis.
All I get from Telkom is that all traffic went through my port, therefore they are not going to investigate the matter any further. What totally frustrates me is when you ask if they can trace where a specific download was made from (there were a few in excess of 200mb last month, none of them done by any of us and twice on days that we were not at home), and they cannot tell you. They apparently don't keep track of that information. To me that information is very important.
Maybe I should add here that we run a wireless network at home between 4 computers, all with firewalls, anti-virus, etc. Other than the basic software updates, nothing else is really downloaded onto these computers. My daughter has discovered Facebook, and as far as I can tell, it works similar to Yahoo Messenger, therefore no serious extra demand on the bandwidth - at least not to the tune of 3GB in 2 and a half weeks. Or so I hope.
Anyway, the extra 2GB that I have on standby is really slow. Somewhere in the username it has "2GBsh" and it seems to me that it is shared bandwidth. It is incredibly slow on local and very seldom successful on international. Basically just helps to do mail. They also don't have a solution for me in terms of an upgraded account for this household. I can go for 4GB unshaped or two portions of 3GB shaped, but they don't have a bigger account available (say, 6GB).
As for Capt Niemand, I'm searching... thanks for the feedback, every little bit helps.