After the screen saver kicks in, my monitor is being switched off. When I move the mouse, the monitor is being switched on and grabs the sound. I have to switch back to speaker manually. How do I disable sound via hdmi permanently? Win 8.1 pro with media center, 64 bit
With the monitor plugged in and active, try setting your default audio device.
Right click on your speaker icon in your system tray, click "Playback devices", find your desired speakers, and click "Set default". then, unplug your monitor and plug it back in, and see if the default held.