Hi y'all, I really hope someone can identify/help me with my problem as I have searched but not seen anyone else with the same issue on reddit or elsewhere.

my setup is 2019 Nvidia shield pro connecting to my tv via HDMI and my tv connecting my Sonos Arc via EArc with Earc toggled on and in passthrough mode. when I first turn the system on, it works fine. When I play content in dolby surround (I am not sure if it happens with DTS as I don't have any content in DTS audio), whether it be my own files or a streaming app, the audio works fine.

However, when go back to the menu, the system sounds and anything in stereo pcm such as YouTube sound comes out extremely crackly and poppy to the point it might even damage the speakers. the strange thing is that when I go back to dolby surround content, everything sounds fine, but the only way to fix the system sounds and YouTube (and I assume anything not encoded in dolby audio), is to turn off Earc, or switch from passthrough to auto and then back to passthrough in the TV settings.

Some other interesting things, if I turn on dolby audio processing in the Nvidia shield, the problem stops, so I think it has something to do with the passing of unprocessed audio. I've tried using different HDMI ports for the shield and that doesn't help. I bought all new high-end HDMI cords capable of passing 48gb/s and the issue has persisted.

any help/insight/theories would be greatly appreciated as I am not even sure who's customer service to reach out to as I can't quite tell where the problem is.