Update: I hooked up the WiiM Ultra, streaming from Amazon. It appears to be working "OK" although the lag time when you select a different track is much longer than the way Bluesound used to work. I noticed a couple of times the song had to be pressed a couple of times before it would play. The album cover shows up on the device before the song plays. I was jumping around quite a bit changing songs to try "break" it to see if it greys out etc but that has not happened (yet). This is a very prelim assessment since the WiiM just arrived but it is functional with Amazon. I have only used headphones to test it so no comment on sound quality although the sound through inexpensive headphones sounds quite decent. So .... either the Bluesound implementation of Amazon is broken or BlueOS v 4 and its app are junk. The WiiM unit appearance is nice, but the box feels plasticy. For $327 don't expect much more.
