hey cyrus m8 i had an engineer come out this morning he stuck his meter on and said the analog signals were to high he then said i needed a filter of some kind and went to his van came back and put this thing in the line going to my cable modem called a "Forward Path Attenuator 10dB" also says this on other side "FLD5W digital signal conditioning filter" also has a website on it
www.technetix.co.uk my internet seems fine now but only been about 30 mins since the engineer has gone so there is still time. i also asked him what had caused it he said upgrades in the system, sounds to me like most peeps having same prob since upgrades.
hope this helps
Chris