@HuxleyTunafish -- think that you have the "XB7" --> https://support.shaw.ca/t5/internet-articles/equipment-info-fibre-gateway-2-0-xb7/ta-p/29898
I have the same device, and I have no problems.
First, contact Shaw [1-888-472-2222 or www.shaw.ca/chat ] and get them to remotely logon to the XB7, to view its internal statistics. Maybe, the Rogers/Shaw Agent will find something, and will ship you a replacement. Or, they may schedule a technician to do a "site-visit" to inspect their infrastructure and your devices/wires.
Do you have a UPS (Uninterruptible Power Supply) connected to a wall-outlet and your cable-modem, to provide "smoothed" electrical power to the cable-modem?