Must not have the right configuration file. That's crazy.
I get 130 Meg's with comcast, but I pay for 105
I got a new Charter modem about a month or two ago to replace my owned one. They sent me an Arris TM822.
My speeds went from 30/3~ to 60/4~ without any other changes. My owned modem was only capable of 30mpbs maximum.
They no longer charge a rental fee for their modems, so it's no longer worth purchasing an owned modem to save money.