I’m having exactly the same problem. I use WIndows 11. and I use my laptop as a second screen.
The laptop’s sound has this same type of audio distortion. I tested it on an Android tablet and the sound is perfect. but not in the windows version.. I have the most recent versions of spacedesk installed on my PC and my laptop
I made a video to show the problem. I showed that my laptop has normal sound, when I play some audio on it. but when I use it as a second screen using Spacedesk, the sound from my PC (server) is reproduced with a lot of distortion on the laptop (client)
video:
