Screen brightness control greyed out
Mac BookPro 15 inch. Big Sur fully up to date.
Frequently upon wake from sleep the screen brightness control is greyed out. The brightness cannot be adjusted from the keyboard, nor in display properties. Only a restart will restore functionality. I have reset the SRAM/PRAM, but this quirk persists.
Has anyone else had this issue? It only started with an upgrade to Big Sur from Catalina.
MacBook Pro 15″, macOS 11.4