"atc98092" wrote:
Couple of ideas. My Samsung allows me to turn the display off without turning the TV off. You might see if yours has the same function. The other thought is to disable CEC control in the Roku. I'm assuming turning the TV off doesn't turn your AVR off by default, as mine does. But it sounds like the TV is sending a CEC command to the Roku which is stopping playback. In the Roku Settings menu, go to System/Control other devices, and disable 1-touch play. See if that makes a difference.
I fully understand wanting to just listen to music without the screen turned on. This $20 device does the job nicely.
https://www.amazon.com/Extractor-Optical-Toslink-Amplifier-Soundbar/dp/B082B8799C