Since TvOS 16 upgrade, my tv is losing the HDMI connection, with black screen and intermittent audio

Hi, since I upgraded my tv HD to TvOS 16, my device has been having some problems. It seems to be losing the HDMI connection at times when the screen would go momentarily black, like when I hit the menu button in a streaming app, or at the beginning of a YouTube video or a YouTube ad. For example, if I select a YouTube video, the screen goes black, audio returns part way through the ad, then I might see a little of the ad, then the image and audio cut out again, and I miss the beginning fo the video, with the audio returning before the image.

In other apps, if I hit "Menu," it just hangs for a few seconds before responding. My tv is connected to an NAD M51 DAC to strip out the audio before sending the video signal to a projector, and i can see on the screen of the DAC that the HDMI connection is disconnecting sometimes. Is there a safe way to revert to TvOS 15, or another way to fix this?

Thanks.

(this question is about a TvOS problem, but the website here will only let me select "Apple TV Hardware" as a topic, not TvOS.)