You can change the following entries in the "ProfileOption_profile" file.
Usually this file can be found here: C:\Users\***\Documents\STAR WARS Squadrons Steam\settings

If you can't find the file there, run an Windows Explorer search for the file and you may find it under a similar path under OneDrive instead if you have that backup method enabled.

In the file edit the following settings below. The values below are just increased recommendations but can be tweaked to your liking.

GstAudio.DialogVolume 3.000000
GstAudio.MusicVolume 2.500000
GstAudio.SFXVolume 2.500000
GstAudio.Volume 2.500000