I’ve got an HTPC, running Tumbleweed, with an AMD RX 6800 XT GPU. It’s connected via HDMI to my stereo receiver, that passes the video signal to my TV (audio comes from the stereo). It’s been working great for over a year. A couple of weeks ago, I updated Tumbleweed, and since then, I’ve been having this problem. When I start up the machine, everything’s fine. The HTPC runs constantly (no sleep or hybernate), but we turn off the stereo receiver and TV when not using it. When we turn those back on, now, the screen comes up black with the mouse cursor on the screen. I can use Alt+F1 to pull up the menu, and everything runs fine via the menu, but there’s no GUI.
Any clue what could be going on, and how to fix it?
I have a similar issue when switching to my 2013 Mac Pro running Tumbleweed via my KVM switch. The difference is it still shows my desktop background, but with no menu bar or panel and a notification no monitor was detected. A second or two later I get a notification a monitor has been detected and my panels return. I am pretty sure this behavior started with the 6.18 kernel. Since my plasma session eventually returns I haven’t been compelled to investigate further.
I’m wondering if a hotplug script running in the KDE session might be sufficient to re-probe the offending HDMI output, read the TV EDID, and select a usable display mode automatically.
To try this, create ~/.local/bin/hdmi_hotplug_daemon.shwith
#!/bin/bash
# hdmi_hotplug_daemon.sh
# Runs in KDE session, listens for HDMI hotplug and restores GUI
export DISPLAY=:0
export XAUTHORITY=$HOME/.Xauthority
echo "HDMI hotplug daemon started for user $USER"
# Use udev monitor to watch DRM hotplug events
udevadm monitor --subsystem-match=drm --property | while read -r line; do
if [[ "$line" =~ ^ACTION=change ]]; then
# Check for connected HDMI outputs
HDMI=$(xrandr | grep 'HDMI.* connected' | awk '{print $1}')
if [ -n "$HDMI" ]; then
echo "$(date): Detected HDMI: $HDMI — reconfiguring..."
xrandr --output "$HDMI" --auto
fi
fi
done
Save when done, and make it executable… chmod +x ~/.local/bin/hdmi_hotplug_daemon.sh
Add the script to “Autostart” via System Settings.
It will take effect on the next desktop login. Let us know how that goes as a workaround.
I tried the script you created. At first it seemed to work, but ultimately it did not. After creating the script, I restarted the computer. Once running, I shut down the TV/stereo, waited a few seconds, then turned it back on. It worked. So I shut it off again, and left it. Hours later, my wife turned the TV back on, and it did not help. We got a black screen with the cursor.
Thanks for the suggestion though. That seemed like it should have helped.
The behaviour suggests that when the receiver is powered down for an extended time, EDID is no longer available and the HDMI handshake is not reliably re-established on power-up.
So not a KDE issue, and I’m not even sure if it is with the GPU driver’s EDID handling. As a test, try connecting the HTPC directly to the TV (bypassing the receiver). If the issue disappears, the receiver is very likely the source of the EDID loss.
It looks like you may be correct. I tested it without the receiver, and it appeared to work fine. However, I tested your script in a similar manner (shut it off for only about 2 minutes), and that seemed to work okay as well. I’m going to leave it off for a while to test it again.
What seems strange is that if my wife is watching a show on a streaming service through the browser, when the TV/receiver are turned back on, though the desktop doesn’t show up, the browser window (and, in fact, any open apps) show up normally.
Did you try a different HDMI input on the receiver? Saying this since my Onkyo’s front HDMI seems broken, but through other inputs the same device works fine.
