Nari Wireless Waving Audio Issue

Hi everyone,
I bought a Nari Wireless recently, coming from an old razer chroma kraken.
But I have a problem: when I play youtube videos, univerrsity classes or play videogame, the sound is ok and there is no problem. But when I start listening songs (mainly spotify, but sometimes also youtube songs) the audio starts to become really bad and annoying: it moves, like a wave, up and down in volume (like a wave moving near and then retriting far). Moreover this "sound wave" has ALWAYS the same volume-change frequency (independently from the song or the software) and it is more prominent when the song reaches higher volume (e.g. in the chorus; instead, at the start of the song, the sound is generally great with no problems).
I disabled everything, both on windows and on synapse and spotify, there is no enanchement, spatial audio, thx, normalization, nothing. Just stereo.
To me it seems like there is some problems/bugs between wifi-connection and some strange internal normalization?? that does not appear in the options. (to this end, the headset is way less then 1 meter away, in direct air-without-obstacle direction, from the usb transmitter).
I tryed some tests, and when I reduced the audio bitrate (from windows option), the problem completely vanished (but the sound is obviously crap), pointing to a software/connection design flaw.

Is there a way to fix this problem? Did anyone encounter it?
Thanks for any help you can give me

Eventine