Lots of folks seem to have this problem, including me. Roku tech support seems to be clueless. On mine, it's constant - symbol there on all screens. Wonder how long it will take for them to notice and fix?
It happens on ALL screens. It is constant. No matter the state of the batteries. No matter the time of day. No matter the phase of the moon. The battery symbol cannot be removed from the upper right corner of the screen. Roku type 2720X, remote type RC07.
Please send me a PM with your Roku account email address, and include the serial number of the Roku device from Settings>System>About along with a summary of the issue you are experiencing. I'll be able to assist you further from there.