So installed second pod close to a switch so was able to cable it up. Speed was registering less than 100Mb, which was even worse than the Wi-Fi connected pod!
Decided to start from scratch, switched off the pods, then tested at the hub, still only getting 200Mb. Rebooted the hub and re-optimised the Wi-Fi. Finally got 500Mb on Wi-Fi at the hub.
Switched on the cabled pod, 500Mb. Switched on the Wi-Fi pod, just over 200Mb, which considering the location wasn’t too bad.
Dont know why it wasn’t full optimisation from the start but appears to be working properly now. Just get the last pod cabled and all will be good.