WiFi Issues when Sky Q box connected on Ethernet

[Daz+Butt]

I have issues with connectivity across Sky and 3rd party devices when Sky Q box is connected to my Hub using Ethernet cable. 
If my box is connected over WiFi I have no issues. 
I've recently had my Sky Q Mini box replaced and delivered and this is all now connected but as soon as I plug the Sky Q back in to Ethernet this becomes unusable. 
I'm assuming the Sky Q box is at fault but need this to be confirmed before being replaced. Also when the Sky Q box is connected to Hub by Ethernet it runs very slow and becomes very unresponsive to the Sky remote. Disconnect it and instantaneously it performs and responds as you would expect it to. 

[LJB-C]

Hello @Daz+Butt, I’ve escalated your post to our Community Messaging team who will invite you to a private chat shortly and help you with this. 

Just look out for the colourful bubble to start the conversation. Please be aware conversations automatically close if there is no response within 48 hours.

Here's more information on how Community Messaging works - https://helpforum.sky.com/t5/Did-you-know/Escalating-a-post-to-a-Sky-expert/ba-p/3711147#M141