XLR Switch Grounding

[Maki]

I'm building an XLR 2-in-6-out switch to have an easy way to switch between 2 DACs and up to 6 amplifiers. Is it safe to connect the two input (DAC) grounds together? My existing switch box from Douk Audio has all the output (amp) grounds connected so I know that part isn't an issue. Also, for the 2 position DAC switch - should it be shorting or non-shorting?

 

[Speedskater]

An XLR interconnect system doesn't have a ground terminal. Pin #1 is the shield and should be attached to the chassis at it's connector.

An input selector should be non-shorting.