The Fire TV Stick 4K Max is a great new device, but if you picked one up during the ongoing $34.99 sale and think the picture looks a bit soft, then you might be facing a bug that some people are experiencing. If you have a Fire TV Stick 4K Max connected to a 4K TV, take a second to check that it is actually outputting in 2160p resolution because some devices, including mine, seem to be switching down to 1080p even though they’ve been set to use the best resolution.
It isn’t clear what specific circumstances cause this bug to occur, but I’ve found my Fire TV Stick 4K Max outputting in 1080p on at least 2 different occasions, even though its resolution setting was set to “Auto” and it was connected to a 4K TV. Others are reporting that even when they manually change the resolution setting from Auto to 2160p, the setting sometimes reverts itself and switches to 1080p. The bug and unwanted resolution switch seem to only occur when the Fire TV Stick 4K Max is power cycled, but I can’t be certain.
Since this is a bug with the display settings, you can’t fully trust that the Fire TV is outputting the resolution it says it is set to, so you should use some other means to verify the actual output resolution. If your TV doesn’t have an easy way to tell what resolution the Fire TV is currently outputting, you can open the Developer Tools Menu, enable System X-Ray, and look in the upper left corner. I’ve found this reading to always be accurate, despite what the settings panel says. If it reads “2160p,” then you know you are set to the maximum resolution.
Switching the resolution setting, found under Settings > Display & Sounds > Display >Video Resolution, from Auto to 2160p seems to fix the issue, at least temporarily. One issue with doing that is the Fire TV Stick can no longer automatically match the content’s frame rate, since that requires the resolution setting set to Auto. A solution is to switch to the 2160p setting, then power cycle the device (selecting restart from the menu isn’t enough), then switch it back to Auto when it powers back on. This should keep the resolution at 2160p while it is set to Auto.