Streaming app issues after tvOS 26.0.1 update- apple TV 4K

I finally "fixed" the issue, and by total accident of course. Had nothing to do with Apple TV itself, but the Onkyo receiver (RZ-50).

Basically when I opened the receiver's app, it wasn't showing the incoming signal as "Dolby Atmos", so I started cycling through the DSPs (THX, Movie, Game, etc). That's when I first noticed the issue with the dropouts that I described. I tried different HDMI cables, different inputs, different ATV4K boxes, and it all created the same issue. I even tried it on different inputs on the receiver. For the record- I also have a Panasonic 820 4K player and everything was okay, so it's definitely an issue between receiver and ATV4K.

Anyway- once I went back to the beginning, I started cycling through all of the DSPs until it came back around to just true straightforward Dolby Atmos. No manipulation whatsoever- just process the signal from the Apple TV and go, and the issue has been resolved.

Essentially- if the Onkyo receiver was trying to manipulate the incoming signal from the Apple TV4K- no bueno. This is definitely new since the update, so maybe it's something Apple can fix? But the issue seems to be with the Onkyo being moody.

Quick update. I moved the downstairs box that didn't have the issue upstairs, and still had the problem. So there is definitely a compatibility issue with my current setup.

Setup that isn't having any issues is Apple TV 4K (3rd gen) to Samsung TV, then connected to Sonos Arc. No issues with video or audio dropping out after update to 26.0.1.

Upstairs is TV4K (3rd gen) connected to Onkyo RZ-50 via HDMI, then HDMI out to Hisense PX-1 Pro Projector.

The apps that are not effected are Disney Plus, YouTube, and YouTube TV. The Apple TV app doesn't have an issue when playing Apple TV+ content, nor does it happen with some of the newer movies in my library. I mention this because some of the older movies have the same dropout as the streaming apps. The only pattern I've found there is if it's a newer move with iTunes Extras (has a start screen similar to a DVD), then there is no issue. But if it's a movie that starts playback immediately (no initial screen where you can pick scenes, special features, etc..- the dropout is there.

What's strange on the streaming apps is I can actually start whatever content, and can even watch the trailer. The intro screen to HBOMax or whatever will play, the preview for whatever new show is coming soon will play, but when the actual content selected starts to play- that's where the freeze happens.

TLDR: It's something specific with my setup in a dedicated theater room no matter which Apple TV4K I used. It doesn't matter if it's connected via Ethernet or Wifi, and only certain apps seem to be effected. FWIW- even trying to play Hulu content from within the Disney+ app didn't work- so only native Disney content played without issue.