How to remove noise in speakers?

Question

After my operating system boots, I can hear repeatedly scratch-like noise from speakers. I googled this problem, and almost found solutions somewhere: if I type like a

echo 0 | sudo tee /sys/module/snd_hda_intel/parameters/power_save

in terminal, then type a password, this command echoes "0" and noise dissipates. Solution is deficient since its annoying to type the same command every time when booting. Then I have couple more questions:

1. Should I create a new command somewhere in startup scripts to get rid of scratch? Somewhy I wonder if its a good idea, but if so, is this page what needs to be followed? I dont have systemd, but runit.
2. What does "echo" do in this bash command? When reading "man echo" I knew only, its needed for variables output etc.

P.S. I have Cinnamon DE, if it does matter.

Answer 1

The echo command outputs its command line arguments to stdout, in this case it's piped as input to the following tee command which runs as root (via sudo) and puts the "0" into the file /sys/module/snd_hda_intel/parameters/power_save.

From https://forums.linuxmint.com/viewtopic.php?t=186531 the best advice is to add "options snd_hda_intel power_save=0" to /etc/modprobe.d/audio_disable_powersave.conf