Possible Audio Glitch: Sound only coming through soundcard audio port?

This is very weird: I have two 3.5mm audio outputs on my computer. Usually, I will plug my desktop speakers directly into the one on the soundcard, and then my headphones into an auxiliary jack on the front.

Since the latest update, BeamNG only comes through the sound-card port (not the other headphone jack). If I want to play the game using headphones, I have to unplug my speakers, and then plug directly into the soundcard/motherboard port. No settings on my computer's device/hardware manager can seem to remedy this.

I'm not saying it necessarily a problem with BeamNG, but it's the only game I have that this problem happens.
I've tried changing the "audio device" in the Game settings, and although the headphone port shows up in the list, it does not do anything when I select it. I've tried setting it, then restarting the game. Same results.

My RealTek audio driver is up-to-date and I'm using the RealTek Audio manager with all effects/extras disabled. Not really an app-killing problem but it is annoying. I'm not using any screen-capture programs, although streaming in Steam is enabled.

Any advice would be appreciated. I'm using a 64bit Win 10 desktop with Nvidia GTX970,
Core i7-7700 Processor, 16GB Memory, 1TB Hard Drive.

 

I think they might be treated as different devices, but Windows (or Realtek driver) is pretty good at switching between them. In game I selected "2nd Output" as well as tried every other option at (Option > Audio > Audio device)... it still came through only the motherboard port, or was completely silent.

Usually if I plug in my headphones, my Realtek audio manager will let me select that hardware, and it will send the audio signal to only that device (headphones). When I unplug my headphones, the device manager will automatically begin providing signal to the other jack again (speakers).

 

Okie doke. I will check it out once the hotfix comes out. No worries. = ]

Edit: I have submitted my files to support server. My support ID is 20771. Thanks!