The popping is caused by power saving feature that can cause audible pops when your sound card sleeps and wakes up. So in my desktop I disabled this feature!
My sound card is an HDA-Intel
cat /proc/asound/cards
0 [PCH ]: HDA-Intel - HDA Intel PCH
HDA Intel PCH at 0xf7f30000 irq 34
To disable power saving and persist this change after reboot:
>>> /etc/modprobe.d/alsa-base.conf <<< add
options snd-hda-intel power_save=0 power_save_controller=N
To test settings (in my case doesn’t work)
sudo sh -c "echo 0 > /sys/module/snd_hda_intel/parameters/power_save"
sudo sh -c "echo N > /sys/module/snd_hda_intel/parameters/power_save_controller"
REF: https://superuser.com/questions/1493096/linux-ubuntu-speakers-popping-every-few-seconds