Surround Panners in FX Channels

Hi Everyone,
Please help. I am trying to set up a surround sound project and have hit a snag.

I can get my mono or stereo audio tracks to move around the surround spectrum successfully using the surround panner but when trying to add reverb via the FX channels or Group channels it will not play ball.

It will only send out one signal and on the FX channel the surround panner won’t open as it would on the audio channel.

I am setting up the FX channel as 5.1 and it is showing the output as Surround which is the name of my Surround output channel.

I have also tried the same with Group channels to no avail.

I have attached a screen shot of my mixer showing the surround panners greyed out and the panner as it loads if I double click on it. I have taken the Reverb off the effects channel just to check it wasn’t that stopping the surround working.

What am I missing?

Thanks

Paul