I subscribe to Shaw internet 30 plan. Every night, starting about 7pm, the internet speed starts to drop. By the time of 9pm, I could only get 3Mbps out of the modem. The slowness goes away at mid-night. I suspected one of my devices was causing the problem. So I disabled both 2.4 and 5G radio (DPC3848V) and left only my desktop connected to the modem. I also tried rebooting the modem before measuring speed. No matter what I try, my internet crawls when I really need it.
I appreciate if anyone from Shaw can take a look at your side to see what the problem is.