HDMI Audio Extractor no sound

[cesedy]

Hi.

I want to connect my PS4 to PC speakers.
I have an eBay HDMI Audio Extractor - 1.5M HDMI AUDIO EXTRACTOR 4K HD CONVERTER INDEPENDENT STEREO OPTICAL FILL | eBay

When I connect my PS4 in HDMI In port, my PC monitor in HDMI Out port and my speakers in 3.5mm jack, I get picture, but no sound.

Then I noticed, when I connect only PS4 and 3.5mm jack but do not connect monitor, I get sound. But, as soon I connect my monitor, the sound disappears.

I can even see, that as soon I connect PC monitor, the red light from SPDIF port goes dark.

Am I being stupid and do not understand how to connect extractor, or it is just not working?

Thank you.

 

[dangus]

There's a similar thing at Amazon. "HDMI Audio Extractor 4K 60Hz 5.1 ARC HDMI to Audio Optical Toslink SPDIF Audio 3.5MM Audio Stereo Audio Converter Adapter"
The description warns to use an external power adapter if you use it with PS4. Have you tried that?