Yeah if the fader and dimmer aren't in the sound/settings menus, you've got the old adaptor plug problem mentioned in the FAQ.

My Mk2a had this happen last week but it magically corrected itself. David @ Emepg says the leaf switches inside the adaptor plug sometimes stick. I haven't had it happen to my Mk2a yet this week so I hope it was a one time thing.

I actually had it happen permanently in my Mk2 and had to send it to be fixed.