Neither do I.
However . . . . !
There are re-release of my favourite 70's albums, new classical recordings in Hires, on Amazon music, on downloads, that sound pretty good.
Perhaps not because of the higher bitrates etc. but because they are re-mixed, or just better mastered. Now, I have paid the money, and would like to hear them as intended. If they are down-sampled, or sent to BT - you can tell! I could tell.
Upsampling is pretty safe, but downsampling can be detrimental.
It is good to know, for the little money I paid for Wiim, it can do the job, right.
BTW - On my Android phone, with UAPP (usb audio player pro) , I could not make it play to Wiim.
With Neutron, once I managed to decipher its network and streaming method, it became a doddle. I can play bit perfect to wiim with it, no issues.
As I already had said, jRiver, also a bit mysterious, managed to play to wiim, no issues.
But not UAPP! Unless someone could tell me how!