Kwee

Just spoke with AT&T and he changed my MTU to 1472 instead of 1500 on the AT&T modem. The issue is still the same. He didn't tell me he did this I just checked all the settings after he told me he did some configure changes. Going to have a Tech come out and do some testing. it's pointless for these guys over the phone to do some basic test that I can do myself.
I ran some MTU test in CMD in windows at 1472 and 1500 and it's saying "Packets needs to be fragmented but DF set. (100% loss)
if  I run it at 1444 MTU I get (0% Loss) anything higher starts to give me loss. 

I did a full reset on the XR1000 and just changed the wifi name and password. issue is gone now. I always have my kids friends using the wifi so tons of devices always on and off the network.

Great to hear that! Ideally you would set it to the router MAC address and if you're not sure what that is you can look on the sticker on the underside of the router and it will show there. If it's all good now it may have been a one off or peak time congestion but do keep an eye on it.

The fact that your ISP router is showing unstable ping would indicate the ISP router is having issues or there are issues on your line, the XR router can definitely handle those speeds

I restarted the modem and now the problem seems to be fixed. 
 

Ya this is on PC

It's just cached data, it won't affect anything and will be cleared out if it's needed. When you reboot it probably cleared out a bunch of this.

I suspect you've been doing a lot of streaming/downloading or some other high bandwidth application which would account for the received packets being a lot higher than transmitted

They're independent features, unprioritized packets don't mean the same thing on both. Your connection has a little bit of packet loss, which is why you're seeing unprioritized packets on the System Information page. Your unprioritized packets represent 0.01% of your total received packets so it is nothing really, you would not notice any difference with that, it is within normal parameters so you can safely ignore it. As to why others see 0 it just depends on their ISP etc.

Although the number seems big, in comparison to received packets it is a very minute percentage and therefore within normal parameters so nothing to worry about