Liftmaster MYQ Internet Gateway Registration/Connection issues!

[Carmody]

Hi there,

My Liftmaster MyQ internet gateway was working fine until I switched broadband providers at which point it refused to connect to my new router.  I checked the Liftmaster website and confirmed that my Virgin Router (Virgin Hub 3.0/VMDG505) is not listed as incompatible with the gateway.  I have tried different router ports, soft and hard resets of the gateway and even deleted it from my MyQ list of devices in the hope that I could reconnect it as a new device.  All to no avail.  

The MyQ team based in the US say my gateway device appears OK to them and are blaming my "new router operating at a higher speed than the gateway can keep up with". Which is kind of b*llocks as I've actually downgraded my broadband internet speed! They say I need to buy and use something called a "cross over cable".

Symptoms

1. When I try to set up the gateway using the MyQ app by entering the gateway's serial number, I get error code 310. The guides say that means the gateway is on another user's account and unable to register. (Since I have removed the gateway from my account, how can this be? Is this something the MyQ team have to resolve in their own database?)
   
2. When I try hard or soft resets as per manufacturer instructions, the green and blue lights on the gateway flash briefly, then the orange, then nothing.  The green light is supposed to stay on to show the device has connected to my router. There is no problem with power and all ports of my router are operating fine with other devices.
   

Any advice or tips would be greatly appreciated!!!  

Regards
Carmody