Shorting out some SPDIF outputs on a 4 pole jack to a mono jack

[msuffidy]

I have an Audigy 2  sound card. For like 10 years I have been using a mono to digital coax to my stereo. Recently I found out that it there is supposed to be a 4 pole jack with 2 other  SPDIF lines that apparently I am shorting out. I think what my main question is there any danger in shorting out these other 2 SPDIF output lines directly to ground? Are soundcards generally made to be resilient of this? There are 2 examples of connecting a digital coax here from the manual. One of them seems to use the same mono plug I am using. Also this wiring diagram is of unknown accuracy. The ground in other 4 poles often is the 2nd from the wire side. Also, I have enough miscellaneous hardware that I can put in a 3.5 mono jack and connect it to a riser on the card if I wanted to. I am afraid of blowing something as I am sure there is no problem in the first place. I hear SPDIF is usually 0.5 V.

[NiHaoMike]

The output is connected through a resistor network, shorting it to ground will only increase the load on the output drivers by a small amount.