Hi,

I use simple setup for music and TV audio: Apple TV 4k → Samsung TV → Sonos AMP (S2) → HiFi speakers 2.1.

I am using HDMI ARC for interconnection as neither my older TV or Sonos AMP support newer HDMI eARC standard.

As now Apple Music received support for lossless audio (24-bit/48 kHz on Apple TV for time-being), I started to wonder if I have any quality bottlenecks in my setup because of HDMI ARC. In the Sonos app, Sonos system info I can only find such info:

Audio In: Stereo PCM 2.0. 

PCM means uncompressed audio, but what is its resolution, what is sampling rate?

I searched for information on HDMI ARC capabilities in the internet and at best I found articles as this one (https://www.tomsguide.com/us/hdmi-arc-faq,news-26262.html). All those articles have included the same table that shows comparison between TOSLINK, ARC and eARC. In that table it is stated that HDMI ARC audio pass through can have max ~1Mbits/s. If that is true, I am concerned. 1Mbits/s is not so much for uncompressed audio event if it is only stereo.

For example, CD quality is 16/44.1k., so for stereo we need: 16bit x 44100 x 2 = 1411200 bits/s. That is ~1,4Mbit/s.

Does anybody have experience with HDMI ARC? In reality, what max resolution and sampling rate of audio one can expect when using it with Sonos AMP?

Thanks!