Yeah.... but audio is more important!!
I just bought the NS Pro on Amazon.
I think your problem is the TV. Your Sony TV does not have eARC. Standard ARC is hit and miss and not very good.
Streaming results vary from site to site, and with what equipment you are using.
I do not use any streamers like ROKU. I abhor hunt and peck remotes, and the limited number of apps supported.
So what do I use for streaming? Mainly HTPCs. In my theater I use a 4K HTPC that does the lions share of the streaming.
In the great room 3.1 system nearly all of the streaming is via an Intel NUC HTPC running Windows 10. Occasionally we stream via a Chromecast device. Both the TV and pre/pro are older and only have ARC and not eARC. The Netflix app on the Intel NUC supports DD on Netflix and Amazon, as does streaming via our phones or my wife's iPad.
In the theater, most of the streaming is via the HTPC. HTPCs allow streaming from a much wider selection of sites than streaming apps. I belong to a lot of Orchestral sites now, and that demands the use of HTPCs. In addition both HTPCs have a VPN link to the Amazon server in London, to give us a UK IP address.
Now my C class LG OLED and my Marantz 7705 support eARC. In addition the system also has a Chromecast Ultra. The system is 7.2.4.
This is where it gets complicated. The Windows 10 apps for both Netflix and Amazon, support everything short of Atmos.
However Netflix and Amazon will provide Atmos via eARC. Interestingly, steaming from my iPhone using the Netflix and Amazon apps, via the Chromecast Ultra also provide Atmos service.
So you might well find that your problems will be solved if you plug a Chromecast Ultra into your Onkyo, and stream from your phone, using the Netflix app on your phone.
Recently the Berlin Digital Concert Hall, that I subscribe to, has made available 4K steaming with loss less audio. It is superb, with the best 4K picture via the Internet I know of. The audio is superb, with a colossal dynamic range. This upgrade can only be accessed via an app on select high end TVs, and more recently an app for Windows 10. Strangely their app for Windows 10 in not intuitive and frankly awkward. The app on the LG TV is much better and far more user friendly.
For streamed concerts a good two channel stream is fine, as the new DD upmixer does such a superb job. The ambience of the hall is reproduced to perfection, and when the applause starts is comes from all around you.
In the family room we have a 2.1 system with an older TV and pre/pro and ARC, which I do not use. Any streaming is done via phone and Chromecast. I do not stream much on that system. It is mainly for LP CDs, FM and for the grandchildren to game on.
