How do i change the gain of an audio using an equalizer i made?

Im trying to change the equalizer gain of some audio i have but i dont really know how to do that/what that means. This is a picture of my assignment:

ive created a GUI with sliders that i have set up with values of 0 and max and min values of +20 and -20, respectively:

this is the code i have so far and it works perfectly. I am able to set a lowpass filter that i will connect with the first slider wich will control it. I tried multiplying the filter by .01 and it made it softer, i multiply by 20 and it just makes the audio very loud and 'static-y' and distored. Am i doing something wrong? Thanks for all the help in advance. Pic of my code:

Answer 1

[Ajey Pandey]

You may be clipping your signal at your highest gain. Is your gain slider set to dB or to raw multiples? (Is your gain function amplifying your signal by 20db or by a factor of 20?)