@Bacchus28 -- could it be the coaxial-cable splitter(s) inside Shaw's "demarcation box" (where the single coaxial cable from the nearest telephone-pole goes into that box, and where you have multiple cables coming out of the box?
Has Shaw replaced the splitters?
Or, as a test, have they connected your TV-modem directly to the feed from the telephone-pole, to bypass all the coaxial cables inside your home's walls?