How to duplicate audio on two HDMIs?

Question

HDMI

Good afternoon!
I have two monitors, they are in different rooms. Connected via HDMI. The system unit is in a closet in the hallway. It is necessary for me that the sound would go simultaneously to two monitors. (I do not need to split the sound, just duplicate it)
Now I use Virtual Audio Cable for this purpose. It has a number of disadvantages: the sound is always late on one monitor, there is no single volume slider, you have to adjust each monitor separately. In theory, I can stretch the audio cable, but there is no aux on one monitor, and I don’t want to install speakers.

Answer 1

You didn't specify an OS. For Linux, use jack.

Answer 2

MS Windows 7