^ Interesting that the 2017 HD Stick (3800) does support the remote headphone jack (when paired with such a remote), in addition to the mobile app private listening. I just confirmed this too with the new Sticks I purchased. The 4K Stick+ (3810) also tested to work.
In contrast, the 2016 HD Stick (3600) was previously downgraded (with OS 7.5?) to remove the remote headphone jack support. Even after updating the 3600 to OS 8.0, it still does not support any remote headphone jack. Your only private listening choice is using the mobile app.
https://forums.roku.com/viewtopic.php?f ... 08#p552320
2019. I've always had an unusable level of dropouts on my roku 3 at home when on 2.4GHz. It's better on 5GHz, but still often poor, and I think this relates purely to the band being busy. The main thing that seems to help is moving the router to a specific piece of the 5GHz spectrum that's less congested. I also have a roku express and I find the private listening (with the app) much better, and usable on 2.4GHz, though some level of dropouts is still sometimes present.