There’s no possible way you can connect the Mscaler to DAVE via XLR. The connection should be made using two BNC cables. So how are you connecting these two components together - Mscaler to DAVE.
Next, check Lumin settings and turn off resampling/upsampling.
Also make sure the only digital output from Lumin to Mscaler is USB. You shouldn’t have any other digital cables in the Lumin. In the Lumin menu select USB under Digital Audio Output Settings. All other connections should be set to Off.
Refer to manual here
https://www.luminmusic.com/manual/general-settings.html