D-sub 25 to patchbay grounding question

[andre tchmil]

hey guys.
How would you connect ground in the following configuration :
Mic lines to patchbay , ground  already connected on both sides.
From patchbay to converters , where to ground ? I'm going from the patch to d-sub 25.

Then from converters output to patchbay. Where or better how to ground ?

thanks for your input.