I have had my Roku 3 for at least a couple of years now. I have been using the headphone jack on the remote quite a bit lately and it really chews through batteries which I guess is to be expected. However, I noticed what seems to be odd behavior.
First, regardless of what batteries I put in (Duracell, Energizer, or various rechargeables) the battery level on the remote never reads much past 60%. I recently tried some AmazonBasics high capacity rechargeables and they pegged the battery level at 62%, the highest level I have seen so far. Shouldn't this meter get to 100% at some point?
Also, the other day I put some freshly charged batteries in the remote in the morning, battery level 62%. Then, later that same day, without having used the remote or Roku, I checked the battery level again and it said 51%. It lost 11% sitting around doing nothing for about 9 hours or so. The headphones were not plugged in during this time (I always unplug the Roku headphones from the remote when I am not using them). Is that normal behavior or is it possible something is wrong with the remote?