Output to two sources?

[Psittac]

Title say's it, how can I have two "default" audio output devices? Don't want to google, prefer interaction.

 

Anyways I want to have my output on all devices, DAC/DAC/headset

[emosun]

passive splitters

[Psittac]

on my machine I have two usb devices, and one 3.5mm/onboard output (headset so 3.5mm input as well).  Was looking for a software option.  When I was running onboard audio only I could put the same source to both.

 

On my friends machine it will be usb and onboard/3.5

[emosun]

If I may ask why does the system have 3 audio output devices? Surely it could use one and be split from there forward.