This has started to become an annoyance from day to day. I have an Asus PB258Q connected to my laptop through HDMI. Starting the computer from new with the monitor connected automatically selects the Asus as the default sound device. However, if I were to leave the laptop on sleep overnight the monitor would then turn off which also removes itself as a sound device. Reawakening the laptop does not bring back the sound device even though the monitor turns back on normally. There is no way to get the sound device back unless the laptop itself is rebooted. It can be reproduced without sleep mode by simply clicking the power button on the monitor to turn it off and back on. When it turns off the sound device disappears (makes sense), but when turning it back on the picture appears but the sound device does not.
I have tried:
- Unplugging HDMI, turning off monitor and back on, plugging HDMI back in. Nothing happens or changes.
- Unplug HDMI, uninstall PB258Q audio device (device is hidden even when HDMI plugged in, no disable/enable), plug HDMI back in. Nothing happens or changes, audio device does not reappear until I restart laptop.
What is causing this and how can I make it so the audio device reappears?
Edit: Some additional information I've come across is one of two High Definition Audio Controller drivers (under System devices) has an issue when the problem occurs. Turning off the monitor removes the ASUS audio device (under Audio inputs and outputs) and the High Definition Audio Controller. Turning the monitor back on results in the High Definition Audio Controller reappearing with a problem icon. Running the Hardware and Devices troubleshooter sees the issue but does not find anything to fix. Uninstalling the problem device, then turning of monitor off then back on results in neither device appearing in the devices until full restart.