My Actiontec T3200M is acting strangely with my Xbox One

[wireless]

Everything was running great, until the last firmware update. I'm on a dedicated, wired connection between the modem and the Xbox. I have the 25Mbps plan, and that's what the Xbox was showing in speedtests, and downloads.

Something happened with the last firmware, and I had to reset the modem using the button at the back. Now on my Xbox, I'm getting download speeds of only 1.5-2Mbps. I have an open NAT, plugged into the same port, nothing has changed, except speed.

Any suggestions?

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