I have a Roku 2 (model 4210X) running the latest software version (9.3.0).
Every time the device is powered on or restarts, I see the "Welcome" screen and must complete the linking and setup process all over again (including pairing to a wifi network, adjusting display settings, entering the code on roku.com/link, etc.). Each time, I fully and successfully complete the setup process and am able to use the Roku normally - until the next time I want to use the Roku. Then I have to go through the setup process again.
Any suggestions? I've confirmed there are no software updates available, and I've also tried restarting the device and unplugging/plugging back in.