The 3920 is the Premiere. This player works with both the basic IR remote and the WiFi Direct voice remote. Your basic IR remote should work with it, assuming it has the Roku codes built in. If it does, the packaging should have stated Roku support. As to what the codes might be to use on a Roku, I have no idea. I did a quick web search, and both 1966 and 1992 were listed on a post. I can't promise either will work.
Since your Roku is WiFi only, you must have a working remote to get the device connected to the network to complete the initial setup. You mentioned a pairing button. The IR remote will not have a pairing button, as you don't pair an IR remote. They just work. Any remote that uses RF (WiFi or Bluetooth) would require pairing.
Dan
Roku Community Streaming Expert
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