Audio Mixer works good in unity but not in build

Hi,

I am creating a volume control using a slider that stores the values with PlayerPrefs. Everything is good while testing in unity. The sounds in the same scene as well as those in different scenes change their volume. The issue is that after building, the volume works only in the same scene. I am a newbie in unity and I can't figure out what could be the cause. I couldn't find it on the internet.

Can you help, please?

Thank you,

Alex