In my case crackling sound was caused by audio-card goes to sleep for power save reason at startup and so it crack when return active so probably most crackling issue will be solved with this comand on terminal:
echo options snd-hda-intel power_save=0 power_save_controller=N | sudo tee /etc/modprobe.d/hda.conf
terminal will respond : options snd-hda-intel power_save=0 power_save_controller=N
now restart your system and see if issue is solved