This tutorial will guide you in adding musical sound cues to your level. For more technical information, refer to Epic's Unreal documentation.
Sound cues Edit
Make sure your audio track is a Waveform Audiofile Format (.wav) file and is stripped of all metadata.
In the editor, open the generic browser and then at the dropdown menu, click on File and then New.
You will be greeted with this window
A - The name of your package. In this example the naming convention is M for music, then CM for custom map. You can also work in the internal package of your map by typing in the name of your map file.
B - This is the name of our audio file. Make sure it has no special characters or spaces.
C - You can auto create the cue to save time.
D - Make sure this is unticked if you plan on using AutoCreateCue.
Note: Attenuation nodes are only used for sound effects, as attenuation is a system which determines the volume depending as to how far away the player is from the sound effect. This is not needed for music.
Once you're done, click on Ok (or Ok to All if you are importing more than one file) and you're ready to continue.
Right click on the empty space in the generic browser and then click on New SoundCue.
This time I added M before the name of our file to differentiate between our audio file and our sound cue. Click on Ok once you're done.
Right click on the newly created sound cue and make sure the sound group is set to InGameMusic. This will allow the engine to differentiate this cue between other sound effects and also allow the player to control the sound of the music through the options menu.
Right Click on the sound cue and click on the Sound Cue Editor. This will open up a new window. To add your audio file to the cue, click on your audio file once in the generic browser, then right click in the SoundCue editor and then click on SoundNodeWave: "youraudiofile".
Next, in the empty space, right click and click on Looping.
Connect the nodes and then close the SoundCue editor. This will allow our music to loop indefinitely.
Right click on the SoundCue and then click on the properties. Set the VolumeMultiplier to 1.
This will give us easier control over the volume through Kismet and will make our music have the same volume as the audio file.
Open your level's Kismet. Right click, New Action, Sound and then click on Play Sound UI. If you have trouble navigating Kismet then refer to Epic's Kismet Guide.
A - Connect the Play Sound UI node's Play connection to the event which is supposed to fire up your music. In that case, the music plays when the map has been loaded. If you want to stop your music, connect the Stop connector to an event that should be triggered when your music should stop.
B - FadeInTime, adds fading when your music has been fired up. FadeOutTime fades your music out when it's stopped.
C - Add your music to the Play Sound UI node by clicking the SoundCue you have created once in the generic browser, then click the green arrow as shown here. The magnifying glass navigates to the referenced asset in the generic browser. The box next to the magnifying glass clears the field.
D - Control the volume of your music through the VolumeMultiplier property.
And you're done. Here's a tip, you can clean up your Kismet by hiding unused connections. Right click on a node and then click on Hide Unused Connectors.
If you want to unhide a connection, right click and then click on Show All Connectors or individualy Expose a connection.