There is more to a good connection than just raw speed or a potential speed. Some things are more sensitive to latency, broken connections, retires etc.
I honestly do not know this for a fact, but I will say in my experience it seems AS is a little more sensitive than just pulling down your typical stream.
My point here being I suggest digging a little deeper into your network. You might try running a speed test at Ookla just to see what it comes back with. Understand that only measures available bandwidth so only run that when nothing is going on within your network.
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https://www.speedtest.net
That site does provide a latency number, but as a measuring stick I often times like to ping Googles DNS at 8.8.8.8 to see what it comes back with. For example I normally get about 16ms on that from my PC. So I know if I see that number spike way up that something is wrong.
Sometimes routers, especially older/cheaper ones, will not handle the speed your connection is running at. And on that note often times a firmware update from time to time is ALWAYS a good idea for those.
If this is a connection related issue (and not a PC related one) I would suspect that your connections are getting broken. This would not bother regular stuff so much but something that is more sensitive it would. This is more common on things like cellular and satellite. But you said Spectrum so I am assuming cable. So I would suspect one of the tests above to show something. If everything checks out clean I would say it's really leaning to PC issues.
Everything I mention above is good to do anyway from time to time to check up on the health of your connection so none of that is a waste. But the best way to solve the mystery is provide a log file with the latest version as RF1 mentioned.