The KAudioMixDesk plugin provides convenient Editor Utility Widgets for audio mixing. They can be run and docked in the editor and some will automatically connect during Play-In-Editor. These tools populate automatically from assets present in the project and can modify assets properties.
To run these widgets, with the main Level Editor open, open the "KPlugins" dropdown and select the widget you want.
The soundboard gathers all assets inheriting from Unreal's USoundWave class into the sound list. Natively, this includes sound waves, sound cues, and MetaSound sources. These assets can then be selected, modified, and preview played in the editor. Sounds can also be played simultaneously for relative volume balance. Changes will be reflected in realtime during playback both in the editor and any instances in PIE. A list of sounds currently playing in the editor is also kept so you can manage playback of sounds you are previewing. Note that this list does not include PIE instances. You can also open assets if you need to edit more directly.
The soundboard also gathers all attenuation assets and similarly allows you to modify them and have those changes be reflected during PIE. Note that some properties are not shown and you'll either need to open the asset or modify the visibility settings by clicking the gear icon next to the search bar.
The "Show Debug" toggle enables and disables Unreal Engine's built-in audio visualization support during PIE by calling the native console commands found in "au" and "au.3dVisualize".
Use this widget to do general volume balancing and attenuation adjustments on assets themselves.
NOTE: Because this widget is self-generating when initialized, if you update what assets exist in your project you'll need to restart the widget. Not doing so may be unsafe and could cause errors or crashes.
The mix console gathers all USoundClass and generates a hierarchical mixer that matches the inheritance structure (aka bus routing in audio terms) of your Sound Classes. You can then use the faders to adjust the volume of any USoundClass for mixing. These changes will be reflected in realtime.
If your USoundClass has a Default Submix, a meter will appear that allows you to montior the output of the submix.
NOTE: Because this widget is self-generating when initialized, if you update what assets exist in your project you'll need to restart the widget. Not doing so may be unsafe and could cause errors or crashes.