I have the opposite situation. I must disable the screen saverAND enable the 20 min power saver to, get my Ultra to turn off after the 20 minute timeout for no activity.
What I find, with my Ultra connected directly to my Onkyo A/V is once I turn off (place in Standby) the A/V receiver, The Roku is "seeing" some signal on the HDMI connection and turning itself on. Based on my observation it will power off after 20 min. IF I UNPLUD the HDMI it will power off immediately. So not the same solution as described by others. Its obvious that the device the Ultra is connected to is a driver in this issue as well.
On one TV, I have to have the screen saver off and power saver on; on the second TV I have to have the screen saver and power saver both off. The only difference is the first (power saver on) is connected to the tv through an HMDI switch and the other is connected directly to the TV. With the second, with power saver on the Roku turned its light back on after twenty minutes, so it’s apparently acting as a toggle.
I have a similar issue. The power light is always on, unless it isn't. I have tried all of the listed workarounds, but it just does what it wants. I'm ready to return the LT and put my reliable Premium Plus back in service...
On my 2020 Roku Ultra (4800R) the light worked as it should after turning off the screensaver and leaving power saver on. (The problem was caused by the updated software).
I decided to get a 2022 Roku Ultra since the 2020 model was getting flaky (freezing screen going black, unresponsive etc).
I set up the brand new 2022 model (4802X) yesterday (all defaults) with included cables and with the new power supply, it updated the software automatically. This morning the light was still on.
I then turned off the screen saver and 2 hours later the light was still on, I turned the screen saver back on and turned power saver off and now it works as it should, the light goes out. Brand new and defective right out of the box. I will use it with power saver off to prevent overheating and early power supply failure.
I have been riunning this Ultra LT with screen saver on. When I start up the LT the screen saver shows on my TV screen. If I use power saver, my LT will not power on. Sure are a LOT of bugs for a "new" product.