There is sparse documentation on the operation, but if I had to guess I'd say they use Wi-Fi direct like the remotes. If so, they'll use whatever channel your TV is using, but they make a direct connection with the TV bypassing any of your network equipment. You might want to try "Fast TV start" under Settings->System->Power to see if they do a better job of maintaining their connection. Also, if your equipment's Wi-Fi channel is set to "Auto", try picking a channel and sticking with it.
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