My former internet provider, Canal Digital. I lived in an apartment with my best friend for a couple of years and then with two others for about 3 years after that and we always, always, always had trouble with our internet connection. A friend of mine, who also happens to be the one who installed the internet in this house (it was newly built when me first moved in), said that the provider had met their quota and then some in this area and as a result, they had sold more bandwidth that the central could handle at peak traffic especially at certain times during the day and evening.
We called customer service/support dozens of times, they always blamed our computers and phones for the issues, they claimed that two PC nerds were so dumb that the internet connection was running slow, or sometimes not at all, due to their PC's not "being set up correctly". At one point, I had a brand new rig, only weeks old, and they used the same explanation.
When the two others moved in and started buying a bunch of gear, we came to the point where the following devices had "problems" and not the connection/central itself; one PS3, one Xbox 360, two desktop computers, two laptops, one iPad, one iMac, two smartphones. So, we happened to have 10 faulty devices in our house, I wanted to scream at the idiot on the other end of the line! The turning point came when the father of the girl we lived with came over, he happens to be a chief engineer for Scandinavia's biggest telecommunications company and he brought a bunch of diagnostics equipment and set it up for one week, he quickly concluded that the central was overworked and that Canal Digital had sold more bandwidth that they could provide in the area, latency issues caused the speed to often go from the 25/5 Mbit we paid for and down into 0.9/70-80 Kbit territory, which is utterly atrocious for the price (40$ per month for this crap) and he reported his findings to the provider (along with over 70 incidents in one single week where contact with DNS simply vanished for up to 20 minutes at a time). Two weeks later, technicians arrived at the central and upgraded it, after what must have been thousands of complaints in the area over several years, and the internet worked really well from then on. And then I moved out about two months later... 
Anyways, companies that instruct their customer service reps to blame the person making the complaint are the worst kind, it's so cheap and cowardly and most people don't have nearly enough insight into the problems they're experiencing to ever put up a fight, and fewer still have a father who is a senior engineer for Telenor. It ended well but took its sweet time.
