While the 4 is still a respectable performer, I agree that moving to the 2016 version of the Ultra would be better. You get everything the 4 had, no fan (although I could never hear the fan in mine) plus 4K HDR support. Also, if you stream any local media, the Ultra supports H.262 video, while the 4 does not. And as I said, the only way I ever heard the fan in mine was to pick it up and stick my ear right next to it. Even then it was just a whisper.
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My personal suggestion is it's time for an AVR update to support HDMI audio. One less cable to run/become disconnected and who knows what audio support Roku might add in the future. My newest Yamaha supports 4K/HDR and all of the audio codecs, and I paid less than $300 for it. Sometimes you have to bite the bullet and update!
Dan
Roku Community Streaming Expert
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