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I teach a zoom class and my voice is so lagging behind the actions I am doing. I was advised last week the problem had been addressed but it is not
I have just completed a remote speedtest on your modem.
The speedtest result was as indicated which is excellent for the plan you are on being 25M down / 5M Up
You could possibly have a Wifi issue or your Phone / PC are too far away from your modem.
The best method would be to connect your Laptop directly to your modem via an Ethernet cable.