Thanks everyone (so far) for your reassuring answers.
John, specifically to your comments: I do have the excellent Shaw-supplied Hitron CGNM-2250, which they now offer for free for the Internet 30 plan and upward. The Shaw-supplied (on Internet 5 and 15, and previously on 25, 30, and 60) crappy Cisco DPC3825 (which was designed by a company that Cisco later bought) has indeed caused problems for VoIP customers of mine.
Were you referring to the crappy Cisco DPC3825, or to the allegedly much better Cisco DPC3848V that Shaw had been supplying for Internet 30 and upward before they brought in the Hitron CGNM-2250?
By the way, the Hitron CGNM-2250 allows configuring 1 or 2 of its 4 ports to be configured for straight IP pass-thru, so no reason to ever kick this modem/router into bridge mode. I've been doing exactly that for the last few months with LAN ports #1 and #2 on my Hitron CGNM-2250 (on the Internet 30 plan) - Shaw was kind enough to give me two extra IP addresses for this purpose.
In the meantime, I also just switched to the Internet 150 offer. So far so good - no hangups yet - and I'm getting 8-11 ms ping (as before), 93 mbps down, 16 mbps up, and continuing excellent VoIP, on my retained Hitron CGNM-2250.