Interesting point. Might boost the cost though if there are several mixes. On my old home system there were several different mix settings, but that's after the fact and isn't really going to effect the core mix. What you are proposing is the flip of that. Or, maybe the solution is at both ends?The sad part is it should be possible for one file to carry multiple mixes, not unlike how an image file can carry multiple processings via layers. Or, alternatively, carry mapping information so the mix can be varied on the fly based on a profile of the playback device.