Change Receiver from Wireless to LAN connection

Hey

So I have a receiver in the loft (wired to the bathroom speakers), its currently wireless but will only connect to the wireless downstairs... the wireless in the loft a couple of metres away from it, it can see but won't connect (SB Radio connects fine to it) so the wireless level is average. Next to the receiver is a LAN switch, so i want to flick the receiver from wireless to LAN.

I've looked at UDP Tool but it seems broken and throws up a lot of errors and doesn't find the receiver. Can I SSH into it and change the setting somehow? I tried factory resetting the receiver but that doesn't ever come up with an option to select LAN, just gives me wireless networks options.

How can I do it?

Cheers