Orbi, Powerline, Switch

I have a powerline adapter (Xycel) set up to the main Orbi, and from other powerline adapters (e.g. behind the TV) I have various switches (D-link) connected to the powerline adapter to connect the tv, dish, bluray, fire tv, etc.  It seems like these devices have trouble maintaining a connection to the internet, e.g. it's almost as if only one device can be connect per switch. 

I've assigned fixed IP addresses, but that doesn't fix the connectivity issue.

I've also changed over several of the devices to connect via wi-fi (since they now get a better signal), but still having issues with the devices connected through the switch and powerline - they still drop the connection quite frequently.

While my wi-fi is better, my wired devices don't work as well as they used to.  They all used to have a rock-solid connection with my old router (D-link).