By 'any speed', I assume you're referring to 96khz 24 bits etc.
Which (or both?) output are you testing?
Can you describe your connections?
e,g, for the first issue, my immediate thought is maybe you are using the pro's line out.
The Amazon issue is unusual. How are you playing Amazon? From within Wiim app, or Amazon app? If the latter, chromecast or alexacast?