Scene Loading Very Slow - Sometimes

Sorry this is a bit vague, but I can provide more details if needed. I wanted to put the scenario out there first to see if anyone has any ideas. As part of creating a new game I have two scenes - a Main Menu and a prototype level scene. I have UI buttons in each that allow me to navigate between them just fine with no delay. Recently I added a new scene that will serve as a level selection. It is an empty level (no meshes, lights, etc) with a single button - a Back button to return to the main menu. It uses the same code in its button to load the main menu as the prototype scene. If I run it so the Main Menu scene goes to the new scene it works fine. However, the button on the new scene to load the Main Menu scene takes 15 seconds for the Main Menu scene to load. The oddness is that I can go from my prototype level scene back to the Main Menu scene in about 1-2 seconds. I’m at a loss as to how it can take so much longer to go from a basically empty scene to the Main Menu scene when a fairly heavy scene does it without any issues.

Gooda day.
Do your scene have music and sounds? you must know preloading or not all music and sound make the loading process very slow.

You should take a look at the Unity audio source page and compile your project in diferent audio configurations to see which way is the best for you.

Regards!

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