I upgraded (after being advised by a representative that it would help) from 1G to 2G and am getting about 20 mpbs average. Was your issue ever actually resolved? I am using a router rented from Mediacom.
Same situation here; it's gotten sinificantly worse over the past few months. I upgraded for another 10 bucks; the tech came out and replaced the cable from the pole; I switched out my modem. I'm paying over $100 for 100 mbps and averaging less than ...