Thanks Guys,
Yup- I was using the button in the grab- I know about potential problems with the KC.
I suppose I do not have the problem if you put it like that, David.
The thing is I have been able to get mono bounces all along, but with no confidence. I suppose strictly, the origin of this thread is a slightly different problem, but it was the closest I could find- sorry.
I am not doing the pre-pro on a desk, and so have little 'physical pan control at present.
If I accept that I can only hear monitoring from Output 1 on the left (when it is set to mono) and trust that it is mono, and not a capture of the left channel of stereo, and separately try a gain plug-in set to mono on the Stereo Out channel (which the finder tells me results in a single channel file), then when I combine the two resultant files and phase invert one , there is a residual sound, so they are not the same thing. It could of course just be a slight gain mismatch, but I have fiddled and cannot get it quite right.
This gives me a lack of confidence.... I am needing to perform this operation many times, and lots of littles could end up as a lot, only truly discovered when I am booked into a mix studio!
I just do not remembering experiencing this before; am I imagining that we used to hear mono from both monitors when we hit the mono button, or am I still just doing something stupid?