Screen will sometimes refuse to turn off and I don't get it

Help
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1

Hi! I’m a bit of a newbie at Linux (hence the “easymode” distro), and as such I’m not sure I’ll be able to give all the information I need to. Please don’t hesitate to ask for extra information if it can help diagnose the issue.

I’ve asked around every place I could find for support on Bazzite specifically, but the only response I got was to try asking KDE for help, so here I am. I apologize if this issue is not KDE’s fault. I don’t have a good understanding of what issues may be in the scope of the various parts of my OS: Linux, Fedora, Bazzite, Wayland, KDE Plasma…

I’m using Bazzite DX KDE 44, which comes with KDE Plasma 6.7.1 and KDE Frameworks 6.27.0.

I have my PC set up to dim the screen after 1 minute of inactivity and turn the screen off after 10 minutes of inactivity. It never goes to sleep (I use it as a Jellyfin server, so it would be a problem if it did go to sleep).

Often, but crucially, not all the time, when I walk by the PC after it’s been unused for a long time, I see the screen on. The screen is always dimmed (if I move the mouse the brightness shoots up), so I know it’s considering the PC “inactive” at that point.

Whenever I try to sit down and diagnose the issue (set it to 30 seconds to dim, 1 minute to turn off), it always DOES turn off the screen. But in actual usage, most of the time it doesn’t. I’ve tried closing an app, walking away, and coming back 10 minutes later to the screen still on, closing another app, rinse and repeat until there are no apps running anymore. Steam, qBittorrent, Firefox, Thunderbird, Docker (with Jellyfin and Shoko) none of these is the culprit.

I thought I had a bright idea. I disabled clipboard syncing in KDE Connect. Maybe it was phone usage that woke my PC up. The PC turned off its screen ONCE after I disabled it. I thought I had found the issue.

But the following day it was back.

Another suspect was the HDMI cable connected to the TV, or the Mac laptop connected to the same monitor. Maybe something was periodically causing the monitor to auto-switch inputs (auto-input switching can’t be turned off on this one) which would “wake up” the screen every time. But no, unplugging every other device from the screen did not change anything.

Yet another suspect was USB devices, specifically my UPS’s battery status monitoring USB cable. I unplugged it permanently; I don’t really need that. But no change to the issue. The PC’s screen is still occasionally, unpredictably on when I walk in.

I don’t have many USB devices plugged in: two 8bitdo controllers, keyboard and mouse, a printer, a headset,USB hubs and a switch that I use to switch my keyboard, mouse and headset between my personal and work computers, and another USB hub on an extension that is used to extend USB connectivity to the living room where the controllers are. And crucially, the controllers on the long extension aren’t even able to turn the PC screen back on no matter what I do with them. When I sit down to game and the screen is off, I need to open KDE Connect and move the mouse a bit to see anything.

At this point, my only idea is that having KDE Connect set up AT ALL may be causing the issue. But I can’t afford to turn it off entirely. My phone is how I control my PC from the couch when I need to do anything my controller can’t.

My friend came over and ran a bunch of commands to try and diagnose the issue. He saw nothing preventing inactivity/sleep/etc., and indeed everything was fine (as it always is whenever you sit down and reduce the time to turn off screen to diagnose issues).

I just do not understand this issue and I don’t know how to dig further into it.

2

What happens if you keep watching the screen during this process? Does it dim after 1 min and never fully turn off? Or does it turn off, turn fully on again after N minutes, then dim at N+1 minutes, so by the time 10 minutes have elapsed it’s switched on, but dimmed.

Don’t know if this applies to your environment, but I find that vibrations in the building can be enough to generate a tiny mouse movement and make the screen wake up. (In fact just a few days ago, my upstairs neighbour managed to switch my screen on via vibrations in their floor / my ceiling…)

3

I believe it’s the first option, but I will be back with a confirmation.

I would be surprised, as my building is pretty sturdy/stable and I rarely get any vibrations I can actually feel. But it’s not impossible. What can I do to eliminate this as a possible cause? Is there a way to make the threshold for waking the screen up a bigger mouse movement, or something like that?

4

Not as far as I know sorry, but it would be cool!

To be fair, it’s rare that some completely random movement makes the computer wake.

It’s normally my vibrations through the floor as I walk to the desk, which in practice works as a janky “wake on proximity” :slight_smile:

5

Hello again! Today, after over an hour left alone, the PC had its screen dimmed but on.

I approached it, did literally nothing but move the mouse. The screen went to full brightness.

I sat down and watched it.

After one minute, the screen dimmed.

After 10 minutes, the screen turned off.

To make sure, I waited 12 more minutes. The screen stayed off the whole time.

Then I moved the mouse again, it turned back on, and I came here to type this.

It seems whatever happens to my PC that keeps it from turning its screen off goes away by just moving the mouse once for some reason. While that kinda explains why I’ve had trouble reproducing it so far, it doesn’t help me much.

6

I run my main desktop as a jellyfin server. It is usually in ‘sleep’ when it’s serving video. No problems. But, if your mouse is over sensitive, moving it will cause sleep to end.

7

I see. But at this point I’m pretty sure the mouse doing micro movements on its own and keeping the screen awake isn’t the problem. I just can’t see how that explanation could match my experience with the issue.

8

Since so far no one seems to have much of an idea, should I try submitting a bug report instead?