A provider can have problems... or however their stuff connects to you having the issue, which can cause issues.
What steps have you tried to troubleshoot it?
Sometimes its something as simple as a fried splitter that needs replaced, and everything is good again.
With all your wiring, etc properly and good signals, you should be able to get consistant full speed connection.
EDIT:
Seeing the 63 high .. wondering what plan, the 150?
63 seems to be a number i remember seeing, from people who connected a 10/100 device, to the CGN3