XB7 compatibility issue with TP-Link TL-SG1016DE switch

I have been trying to get an XB7 to work with a TP-Link TL-SG1016DE switch for weeks now. There appears to be some incompatibility issue. Extensive testing with TP-Link tech support has shown that, in a topology that is strictly only Internet--XB7--1016DE--test PC (to ensure that nothing else on the network was causing problems), pinging the XB7 from the test PC will show the packets flowing from the switch to the XB7, but the XB7 does not respond. There is no Internet connectivity for the test PC.

 

Worse still, when the XB7 and the 1016DE switch are connected, any device connected even to the other XB7 ports will not get an Internet connection!

 

The 1016DE switch worked perfectly with the XB6. The XB7 works perfectly with a TP-Link TL-SG108E switch. But the combination of the XB7 and the 1016DE kills the setup.

 

	No switch	TL-SG108E	TL-SG1016DE
XB6 Gateway	Ethernet and WiFi both OK	Ethernet and WiFi both OK	Ethernet and WiFi both OK
XB7 Gateway	Ethernet and WiFi both OK	Ethernet and WiFi both OK	Problems with both Ethernet* and WiFi
* even for a device that is ethernet-connected directly to the XB7 while the XB7 is connected to the TP-SG1016DE

 

It is very discouraging to hear (https://forums.xfinity.com/t5/Your-Home-Network/xFi-Gateway-3rd-Generation-compatible-Ethernet-switches/m-p/3345048/highlight/true#M326017) that the TL-SG116E appears to have similar issues when combined with the XB7. Based on the testing I did for TP-Link tech support, it would appear the XB7 is the culprit.

 

Does anyone know how we can get this escalated within Xfinity tech support?