When I upgraded from KDEneon 22.04 to 24.04, System Settings Sound module no longer has a “Configure” button to allow the creation of a Virtual device for simultaneous output.
This is sub-optimal because that means I have to change the audio device twice (in an application and Systray > Audio) when I want to use a different output than I currently have selected.
Prior to the upgrade, I only had to select the audio device in the System Tray > Audio and VLC would play on whatever output I selected. This is no longer the case.
To further illustrate my point that this may be a bug: The System Tray > Audio widget allows you to check “Show virtual devices” for the output but there are none because System Settings > Sound no longer has the option to create a virtual output.