Digital Surround 5.1 HDMI Ouput throught an HDMI audio extractor is not working

Hi all
well I bought this HDMI audio extractor (JTech-exd2)

video is working fine, audio: only stereo

even when the output format is recognized and set

but, running the test only the right and left channels sound working

could be this some missing settings on manjaro ?
or I have to go to TECH Digital’s support ?

the digital audio goes to my home theater