I did experience the exact same problem for a while, but it was on dialup; never with broadband.
After repeated calls to the 'customer disservice' departent, where some idiot kept referring to his book of stupid things to tell the customer and insisting that there was no limits or restraints on our account, I finally managed to learn that while our contract stated that we had a 24/7 connection, in reality the U.S. owned giant 'did not necessarily intend for the service to be connected to 24/7', and that there was in fact an hourly limit, per-month, on how long we could be connected.
As it turns out, when we reached this undocumented limit, we could still browse the net, and if lucky could download little tiny files; but trying to download anythng of more than a few megs resulted in a sudden squeeze of our available bandwidth down to such a level that communication was impossible. The connection would just hang, until I cancelled the download.
After a few weeks and many angry calls to the company, the idiot there in our little local office suggested that by logging into our account and changing our username (by adding a 0 or a 1 or a 2 onto the username) we could trick the computer system into resetting our usage.
This didn't work. We switched ISP's soon after, and the problem ceased completely.
NOTE: The whole time, the company officially denied that any caps or limits were being applied.
And the thing on top of it all: The bandwidth where I live, in a rural area, is so poor, it literally takes me about 2 weeks, as we speak, to download a CD ISO (most of which happens at night, or when we aren't home). The connection isn't usually much more than 26.4k - 28.8k, so it is virtually impossible to accomplish anything within any reasonable amount of time at this lousy connection speed. There's no highspeed, no cable, no DSL, no cellular, and sattelite is beyond our means.
Last edited by GrapefruiTgirl; 03-22-2007 at 08:37 AM.