What model Roku do you have? Many of the older players don't really report an accurate speed. My Ultra 4800 was the first that seemed to be fairly accurate. Are you having streaming issues with a particular channel, or is everything working OK? If the latter, just ignore what it says for reported speed, as long as everything works OK.
If you are having issues streaming, and you're using WiFi, my first suggestion is to try a different channel on your WiFi router. Most are set to Auto, meaning they choose a channel based on what it detects from its location. If your Roku is further away from the router, it might be getting interference the router isn't detecting. For 2.4 GHz, the best channels to use are 1, 6 or 11. Don't manually assign channels 12, 13, or 14, as Roku devices don't support those and you won't be able to connect at all.
Dan
Roku Community Streaming Expert
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