I have the 2017 version. Today I received the Android 11 update. In the device controls under Advanced Sound options now the Shield allows to pass all the audio untouched over HDMI. Checked on my Onkyo TX-8270 receiver and it's effectively passing all audio on its native frequency: I have sideloaded Apple Music, Amazon Music, Qobuz, Roon, Idagio and USB Audio Player Pro and it changes to the original: 16/44.1, 24/48, 24/88.2, 24/96, 24/176.4, 24/192
I think this puts the Nvidia Shield as a serious and versatile streamer option