I'm only using RJ45. I've tried the reset button on the back as per the manual instructions. They recommended doing this when you use it for the first time and that worked ok as all the lights cycled properly.
I've tried the hard reset method as well holding the WPS button when powering on, but the power light never started flashing.
Read a few other suggestions I found and currently have it without the WAN cable in and just 1 LAN cable, but still no joy. Tried powering off for ages but still nothing.
It currently only has the power light on solid. Left it for ages hoping it'd kick in but not a peep.
Lol, I'm worse of than yesterday, and £200 poorer as well