Although u mentioned u have already PlayBack or other in this regard I am not sure. Although there r various reasons behind of that cause.

Sorry, some texts r missing ! please ignore this and take this one !
Although u mentioned u have already played with the router, but have u interacted with QoS tab of the router, I am not sure, but u can adjust the method of distributing QoS of service by selecting the xbox’s Mac identification and scroll until u see the option to maximize service then apply and save it by following restart the whole process and see if there is any change. Or if u r using any 3rd party SW like PlayBack or other in this regard I am not sure. Although there r various reasons behind of that cause.

first, you need to know what you are subscribing to on your ISP internet connection. It could be a typical cable or dsl connection with low speed. May want to up the speed and pay more. Otherwise, we will have to evaluate the bandwidth that the xbox consume. Is it running in HD? What is the other computer doing? Just browsing or streaming videos? Some streaming efforts are very bandwidth consuming. One way to measure is to download third party software on the PC to measure the bandwidth.

I am not familiar with xbox. Do you experience slowness using the xbox alone at all times? There are peak hours that slows down your internet access.

Possibly your wifi router. You can test by:

1) plugging the laptop into the hardwire ethernet port on the back of the wifi router and see if you still have this issue.

2) measure the bandwidth utilization of your link to see if that is getting saturated

3) If #1 works above, then try to borrow a friend’s wifi router and plug into the ethernet and see if using that Wifi still causes a problem

Best of luck..

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