check the output source setting for the monitor output in the output menu. From your description it sounds as if you have Git/Studio or Git/processed selected. These sources will give you the naked guitar signal with no way to control the volume.
Master Mono is the default setting that will deliver the full signal in mono and controllable from the rig volume and the master volume knob (if the monitor output link is activated in the output menu)
You are spot on I know I had that in the settings. However I have just hit init globals which has removed this and any other silly things I may have done. Thank you for taking the time and I again apologise for such a silly question.