A hundred bucks says you're most likely testing that over WIFI.
(Welcome to Geekzone.)
NonprayingMantis: It's your wifi.
Still could be an ISP issue of you're using the router they gave you and it has a fault, as it would eh their responsibility to fix it. But that's Not especially likely.
But still worth contacting them to troubleshoot your wifi issue.
im more likely to say its your device over the router
got another device you could test on?
did your driver update fix it?