I'm currently experiencing similar problems, last week I added another Gig to my Telkom account, that night I didn't download or upload anything, only played online game Astro Empires for a while then switched my PC off. The next morning when I tried to go online my Gig was finished, so I thought maybe auto updates was maybe on or something. Because I use the internet for my work I had to get another Gig and the exact same thing happened again, within 1 day my time was finished so I went to telkom's adsl site to see what bandwidth usage shows. During the time i was online (from say 10:00 to 15:00) it shows I downloaded 807Mb and uploaded 324mb, although I only checked emails and worked on some designs on the internet. I called telkom technical and they looked and said they cant see anything and that everything was done from my PC as they checked the IP or something.
I then formatted all my drives and did a fresh installation of windows as I thought it might be a virus or something that going through my airtime, that was yesterday. After I was done I got yet another gig top-up from Telkom, that was yesterday afternoon, last night I uploaded 10 designs of about 1Mb each and then I played some poker on facebook. This morning I just checked my email then when I tried to go onto the internet my gig was finished again...=(
Telkom said they will cancel my current account and start a new 1 and I must also go get a different router from them tomorrow morning which they say is more secure than the 105 from them I'm currently using.
I connect to the router with a wireless card so I'm also wondering if its possible that the problem might be coming from the outside, some1 maybe got around the security of the router?
Is there maybe somewhere or some way to get a detailed account of whats been up/downloaded or even just info on where its been up/downloading from. Or the software you mentioned above will that only work to determine uploads or will it work for both?