I believe the theory a couple users have expressed is the culprit. So a question for anyone who is having either a problem with their remote maintianing pairing with the Roku 3, or who are experiencing intermittant audio dropout when they have headphones connected to the Roku 3 remote -
Q: Are you connecting your Roku to your broadband router / cable modem via WiFi, and if so, do you know whether it's 2.4 GHz or 5 GHz, and which channel?
I'll bet 90% of the problems are with Roku 3's that are connected to the broadband router/cable modem via WiFi.
I strongly suspect the problem is because the Roku 3 remote uses WiFi Direct to connect to the box, whereas the Roku 2 XS uses Bluetooth (which is also 2.4 GHz), and the other models use infrared (if you have an infrared universal remote, you can test this by setting it up to operate your Roku 3, and whenever you lose pairing between your Roku remote and your Roku 3, try the universal remote - if it works, the problem is the WiFi connection between the Roku remote and the Roku 3).
The average US home now has about 7 WiFi connected devices, and in a typical home, you'll be able to detect 2-5 WiFi networks, including your own. Do tha math - that means there are anywhere from 14 to 35 devices all chattering away in the 2.4 GHz WiFi range. If you live in an apartment, the problem is much more magnified due to your proximity to other living units in a denser space. There are only 13 channels in the 2.4 GHz range, and every one of them partially overlaps at least 4 other channels. So there is almost always some interference, regardless of which channel you use (some more, some less). There are other devices that also create interference in the 2.4 GHz WiFi channels: baby monitors, bluetooth devices, some cordless phones, wireless speakers, and the most damaging culprit - microwave ovens. The Bluetooth remotes that come with the Roku 2 XS are less susceptible to this interference in part because they use a very narrow bit of bandwidth, and are far less likely to encounter as much inteference as a WiFi device (which uses a 20 MHz or 40 MHz wide channel, and therefore overlaps more of the other channels). The older Rokus that only use IR remotes are immune because they work at a totally different frequency range.
Streaming video is a bandwidth hog, especially in HD. So when you're streaming video over WiFi, you're really hammering the WiFi channel that your Roku 3 uses to talk to your router/modem. So it's entirely possible, perhaps even likely, that you're much more likely to lose pairing between your Roku 3 remote and your Roku since it's having to compete for that same limited bandwidth in the same channel (and who knows what channel your neighbors' WiFi is set to - the factory default for most WiFi routers are channels 1, 6, and 11).
1) Try connecting your Roku to your router via an Ethernet cable instead of via WiFi. If you don't have an Ethernet jack near your TV, you can try an Ethernet over Power adapter (you'll need a set of two). You plug one into an electrical outlet by your TV and plug your Roku box into the Ethernet jack on the adapter. You plug the other adapter into an electrical outlet (not a power strip) by your router, and connect the adapter to a LAN port on your router using an Ethernet cable. Voila! You now have an Ethernet connection. Works great, but the pair of adapters will run you somewhere between $80-$100. Big Box retail stores should all carry them.
2) Try changing the WiFi channel that your router / modem is broadcasting at. All of your devices should automatically change to whatever frequency your router/modem is broadcasting. In theory, channels 1, 6, and 11 have the least potential for overlap, but since they're the traditional defaults, they're also more likely to have high interference than the other channels. So, your next best options are channels 3 and 8. But keep in mind, they overlap with between 6 and 8 channels, respectively. Also keep in mind that microwave ovens really interfere with the higher channels when the microwave is turned on (this includes your neighbor's microwave).
3) If I'm right about the problem being WiFi inteference, there may not be any other solution. I don't know how Roku maintains pairing between the remote and the box - I presume it's some periodic "heartbeat" signal saying "I'm here, are you still there?" Roku might be able to issue a software update that extends the interval between those heartbeat signals so that the box and the remote don't say to each other "I don't see you anymore, I need a new partner to pair with me." Sounds kind of sad and lonely. This heartbeat / timeout could account for remotes losing pairing after an extended period of inactivity between the remote and the box.
4) Perhaps the other solution (if the problem is WiFi interference) is for Roku to issue new firmware that would separate the heartbeat / pairing between the remote and the box to the other WiFi frequency band that the streaming video is not using. For example, if your box is connecting to your router/modem using 2.4 GHz WiFi, the remote could talk to the box using the 5 GHz band. Or if your box is connecting to your router/modem using 5 GHz, the remote would talk to the box using the 2.4 GHz band (this is the optimal solution - 5 GHz is better for streaming HD video, and the heartbeat of the remote would otherwise be largely unaffected by interference in the 2.4 GHz band - it's the continual stream of video at the same frequency as the heartbeat signal that I think is the issue). The Roku 3 (and presumably the remote) have both a 2.4 GHz and 5 GHz radio - so why not try separating the signals?
As for the dropping audio - I am pretty certain that's also because of the WiFi interference. You have video (and audio) streaming from the router/modem via WiFi to the Roku 3, and then the Roku 3 streaming the audio to the remote (when headphones are plugged into the remote), presumably at the same frequency (having a WiFi device that can hop frequencies at the speed necessary for these two stream to be seperate would be pretty complicated and costly). So, the streaming video and the streaming audio are once again competing for the same limited bandwidth at the same frequency.
I have a spectrum analyzer I am going to try at home with a borrowed Roku 3 so I can see what's happening and whether I can see how much interference there is at the time. Kind of a needle in a haystack occurrence, but I'm pretty sure that's what's happening.
So - now that you know more about WiFi than you ever wanted to, how about it? How many of you who are having the remote pairing and/or audio dropping (headphones only) problem on the Roku 3 have your Roku connected to your broadband router/modem via WiFi?