I am not from Intel and I don't have those headsets, but the technical specs do indeed describe things such as 4-Pin 3.5 mm (1/8 inch) Audio Jack Pin Out, where 1 & 2 (Tip & Ring) are the left and right audio, 3 is common/ground, and 4 (sleeve) is the audio in/mic. I use three pin headsets on NUC without trouble - perhaps the headsets you mention include buttons such as fwd/back/pause and/or vol up/down which complicate standards?
Update: I just found iPhone earphones (white with the +/-/center button) and both left and right sound seemed fine when plugged in.
FWIW, my Windows 8.1 is Intel's Display Audio driver (the one I normally use - HDMI or DisplayPort) but Microsoft's HD audio (I don't install the Realtek thing since I typically don't care about headset). The playback device changes to Headphones when I plug it in - there are not much properties since it isn't the Realtek software. I'm not sure that makes a difference. I wouldn't guess that it is a problem with your NUC since you say it is multiple NUCs. Do you have regular headset (three pin rather than four pin) and does the L and R audio come out proper for them? Does the pin from the headset seem to be seating fully into the jack, not impeded by something like plastic or whatever?
Can you tell me where you found the specifications on the audio jack itself? I looked at all of the common documentation and didn't see a darned thing...
Now, for the interesting news.... drum roll...
Since the Windows 7 x64 NUC was working, I swapped out the guts between the two.
The darned jack is bad. In fact, I gather it's always been bad as from day one it never worked.
Looks like I'm returning it.... crap.
Sorry about your jack. Use your favorite search/navigation method to get to some Intel documentation page such as
Then click on Technical product specification for your particular model.
Then go to the appropriate section, perhaps section 1.9 on page 26 for the D54250.
I RMA'ed the NUC today. It was a fairly odd experience:
In the original ticket I mentioned that the jack never worked on the left channel, that I tried multiple headphones, and gave them my address.
I then got an email "Did you test it with different headsets...," "Did it work before, for how long?"
To be honest, it was pretty clear they didn't even look at the submitted ticket. Then we got a phone call, from a heavily accented person claiming to represent Intel who wanted our credit card for the RMA shipping. Of course, my wife, not knowing anything about this, hung up on them.
It was odd. Odd enough that I gave them a credit card, when I called back, that I never use... just in case. Interestingly, the RMA is not being serviced by Intel, but some company named "hibbertgroup.com" from the status email I received. (Not an Intel status email under "intel.com" FQDN...")