When you plug in the Headphone jack, all other audio outputs are muted.
When the Headphones are not plugged in, all audio outputs are normally live, simultaneously. Generally speaking, there is no need to turn off the audio outputs you are not using. If they are not cabled, there's no harm in leaving them active. If they are cabled, then simply select a different input on whatever they are cabled into.
You CAN turn off HDMI digital audio output separately (set HDMI Audio OFF). You can not turn off the Optical/Coax S/PDIF digital outputs separately, nor the Analog outputs.
Thank you, Bob.
I've been reading the online pdf manual and it appears that utilizing Pure Audio only turns off the video processing.
Have you, and / or have others, heard a difference in SQ when utilizing Pure Audio?