Using Roku Model 4800X with Samsung Smart TV (~7 yr old). After using TV thru Roku, if I return to using the TV through Cable mode, the TV will turn off after 10-15 minutes. TV will power up with power button on Roku remote. T.V. will continue to power off after another 10-15 min. I tried unplugging TV, Roku, trying different input on T.V. for Roku. Seemed to briefly help. Issue keeps returning. Currently, Only solution that I have found that remidies this problem, it to pull the power cord out of the Roku device. The T.V. has never shut off when there is no power to the Roku. This is not an elegant solution, but since the Roku device always feels warm after use, maybe better for the environment. Saves energy. Has this issue been experienced by others? To recap: TV constantely turns off when using in cable mode. Never turns off when using Roku and never turns off in Cable mode if power unplugged from Roku device. Also, this issue did not occur until using Roku/Cable for several months.
Have you tried turning off "power saving" under Settings->System->Power? It may be that when the Ultra enters power saving it sends a command to the TV to turn it off. You can also try turning off "1-touch play" under Settings->System->Control other devices.
Have you tried turning off "power saving" under Settings->System->Power? It may be that when the Ultra enters power saving it sends a command to the TV to turn it off. You can also try turning off "1-touch play" under Settings->System->Control other devices.
Thanks, I just turned off the power saving mode. Will see if that helps.