OK, NOT new to buffering and low band width. Did not mean to accept solution to my original question. We've attempted your "Fix" dozens of times - Not working at all - in fact we now have zero internet connection and your service tech can not get to our house for over a week. So - no internet connection for a week! Really? That is AT&T's solution to customer service? I asked the "person" on the phone how much it would cost me to cancel my AT&T service. $180. Definitely not something I should have to pay at all for service I'm NOT getting but it will be worth it not to have to listen to someone on the phone saying the opposite of what this former ATT employee says. This is actually worse than Comcast and that's saying something.
As for your original issue, you cannot REPLACE the router provided by AT&T but you can put a second router BEHIND it if you want.
You might also benefit from a Wi-Fi booster depending on the configuration of your home and where the router is located.
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