Hello PsaCrypt,
when you select the hda_intel device on F6, if you press Esc, then adjust it to how you like the sound.
Press Esc again, now back at the command line, to save the settings so it loads on restart, in your terminal type -
sudo alsactl store
Enter your password when it requests it.
Is it working okay now ?
Sometimes it is needed to open 2 terminal windows, in the first do F6 and change your settings, leave it on the settings screen.
On the second terminal do the command above .
Then close both terminal windows.