Internet crash on first game

Topic says it all. I recently started a new internet plan with shaw as my old contract expired. This plan included a router change that had internet issues at first but since then has smoothed out entirely. The trouble is that Overwatch on this new internet tends to crash, at best, my computer’s connection and at worst the whole router. I’m trying to work out solutions and look through forums but I just wanted to ask a few things:

-Any suggestions on why this is happening or how to fix this?
-Has this happened to anyone else/Is this a common or recurring issue?
-Why is it just OW?

Cheers

This pinned thread may have some insight: