Export Same as source 1x1 10bit lossless

I've run into a problem trying to export a file same as source.

I import the uncrompressed quicktime at 1:1p 10 bit mxf. I make my edits and when I output same as source everything is fine except for the bit rate, which changes from 10 to 8 making the file undeliverable. Why isn't the same as source export keeping it same as source at 10bits?

The only way I can get a 10 bit file to export properly is when I use the black magic codec. Problem there is that I can't direct out my audio so again the file is undeliverable. We recently have gone to a tapeless work flow, so exporting these files at 10 bits is very important, but it seems like avid is incapable.

Is there a solution to this issue? Why doesn't same as source keep it same as source?

Thanks!