Hello and sorry for the late reply.
What are your audio settings on EndevourOS? Also could you send us the logs from the server-side machine?
Here’s how you can gather them: https://kb.nomachine.com/DT07S00243
You can submit them here or send to forum[at]nomachine[dot]com using the the title of this topic as the subject of your email.
Regards,
Jakub