Thanks for your reply.

I am using PEP2. You are right in that if I disconnect the Lumagen and don't make any other changes everything works.

I am using the emitter stick on the Lumagen as it does not have a IR remote input. All other devices are connected through the RFX9600, the remote does not output any IR commands, they all go through the RFX9600 and either emitters or direct cable connections with mono cables.

How do I over come the ground loop, do I need a serial cable which only has three of the pins connected rather than fully wired?