WARNING to potentially be mindful of the volume if you play the video clips.
I added a second audio source because I wanted my main thrusters and side thrusters to be able to overlay different sounds at the same time. For some reason I couldn’t get the win and lose sounds to play as oneshots while I was trying this solution, but in the end I went for a different approach. Tried the old approach now again in isolation and it seemed to work fine so I’m not sure what was going on there.
Anyway, my real struggle was that the side thruster and main thruster sounds together were pretty bad. So I looked at a Unity Learn Audio Mixing tutorial. It still needs some tuning and I’m still not entirely happy with the main thruster sound effect but I think it’s moving in the right direction.
I’m using the Duck Volume effect to make the side thruster sound output lower whenever the main thrusters are running to achieve a better blend.
Instead of assigning audio clips to my rocket I added several individual audio sources to empty objects within my player prefab and then assigned these to my scripts in the inspector.
Generated all of the sound effects with ChipTune which is a bfxr-like sound effect generator. And I used Audacity to cut them a bit.