pretty obvious really… it was only when i was forced to use some cheap headphones (rather than going through my stereo) that i realised how much of a bastard it was to find a suitable volume level to track at: exit renoise, use sound mixer, load renoise, be deafened, exit renoise, etc…(why oh why did soundcard manufacturers suddenly decide that having volume control at the back of a card was SO TWENTIETH CENTURY 
?).
i assume this would be pretty easy to add 
(the thing at the top of the screen doesn’t count; it adjusts the level for the song rather than the program…as far as i can tell. putting that bar at 50% doesn’t seem to give a simple half-volume version of 100%…sounds seem to be processed differently. or this is all in my head.)