I am currently using a Windows 11 PC and a KindleFire tablet with a USB connection.
When I try to play the contents on Amazon PrimeVideo, I can’t get high quality playback even on the main display connected to the PC with a DP cable because it does not support HDCP.
When I disconnected the tablet, high quality playback became possible, so something in spacedesk seems to be the cause.
Does spacedesk officially support HDCP?
(Up until the other day, PrimeVideo was also able to playback in high quality, and I don’t think there were any errors related to HDCP…but the information on the web was also mixed, with both supported and unsupported information.)
Translated with DeepL.com (free version)