Actually leaving out the mute button makes perfect sense. You tell your streaming service 'partners' that there won't be a mute button, and users will quickly tire of walking the volume down and up, so they'll give up and listen to the ads. The partners love it! And then later, after all the deals are signed, you can nick your users for another $30 for that mute button as an 'upgrade' . Roku is one smart company.
Yes, what happened to the mute button. It is shown on the remotes when viewing the streaming devices. Looked at the Ultra to purchase because it had a remote with mute button. Now you review that the remote button has been removed and Roku has not updated the information on their website. I just purchased some 3810R streaming stick+ as gifts, and just checked the remotes, no mute button even though the website shows a mute button. I am returning them. Thank you for the update about the Ultra having the same issue.
The 2019 inventory of stick+ come with mute key, 2018 and before stick+ didn't, sounds like you got old inventory. Best buy has the exclusive stick+ 3811 with headphone jack remote and it has the mute key.
The ultra is no longer on sale, and probably out of stock because of the sale. As I said earlier you can purchase a rc-al7 remote from walmart, best buy, or amazon for $19.88, switch them for the rc-al2 your stick+ came with, then sell rc-al2's on ebay for over $20 a piece and make some of your money back.
Edmund Roku Community Streaming Expert
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Trust me, when the remote batteries start to fail repeatedly, you won’t really give a darn about the mute button at all. This is a common problem they have not figured out how to resolve yet since everyone seems to be conversing about it.