Looking for help with changing volume on layered music

I’m following this tutorial here : Quartz Music System | Course

Quartz seems really cool and I can get up to three layers of music playing and if I trigger a volume it will put the volume up to dynamically add more tracks as I progress in the level.

The problem I’m having is the second I make a fourth track to do the exact same thing blueprint gives me an error.

It’s driving me nuts because the entire thing works just fine until I copy the same node setup that worked on the previous three tracks and try it on a fourth track using the exact same setup. Like there is some limit to how many tracks or audioComponents I can work with?

Here is my setup from the tracks that work.

Copy the exact same thing for the fourth track here and it gets me the error that was shown above.

Can someone please explain to me what in the heck is going on here? am I hitting some hidden limit>?? I can get the fourth track to work but then I cant use that variable to control the volume as that last Volume Multiply is what errors our my blueprint.

Thanks <3

You are encountering an error with the Quartz Music System when adding a fourth track, despite the first three working fine. This could be due to hidden limits on the number of tracks or audio components, variable conflicts, or blueprint corruption. Ensure all variables for the fourth track are unique, recreate the node setup manually, check for any engine limits in the documentation, and make sure Unreal Engine is updated. If the issue persists, seek help from Unreal Engine forums with detailed information and screenshots.