Amazon HD definitely can work with this machine. Unfortunately, it is possible to completely hose the music files. The best solution is either to delete the app or clear out the music data files. I had to do that. In the porcess, I had to up my data download limit with my internet provider because I downloaded so darned much data in a short time period.
A big hassle is watching that darned ring spin the first time you use the app. My suggestion is clear it out; download just a few songs; and test it. If all works, add a few more songs, test it. If all good; then download the rest. Try to not close the app once you get it going; every time you restart the app you go through the wheel issue. Just one of those things.
It also matters is you choose online vs. offline. Experiment with both. The spinning wheel never goes away as an issue; today it took minutes before playing started. The good news is that there are many good things about the app also.
For the person wanting the comparisons; the Chord Mojo doesn't even fit into the list. It is a great mildly warm DAC/AMP but not a fully integrated player. The Mojo oozes power; but not in balanced mode. And it gets warm and is big. The R3 has power coming out of its ears also. But it has a really neutral sound and almost everything on the market is mildly warm so it will sound really different to most reviewers. We have all become conditioned to mildly warm so neutral is something of a shocker.
And as you can tell from my response to the other question; yes Amazon Music's Android app is a pain at times. It is a pain on the Fire HD also. But not nearly as bad on the iphone or PC. Go figure.
