It is true Pipewire is enabled by default, but you are by no means locked in to that decision. Switching back to Pulse is as simple as ticking the checkbox in Garuda Assistant and confirming the package replacements.
If you set up a config file on Arch that got this working for you, chances are the same Pulse config will work on Garuda.
Edit:
I realize I misread your post the first time through. You are still welcome to switch to Pulse as I mentioned and try the fixes you linked, but those threads are some four years old and a lot has changed in that time.
Another option would be to try troubleshooting the issue from Pipewire, like this thread for example: frequent popping/crackling with pipewire / Multimedia and Games / Arch Linux Forums
One final suggestion: installing Wireplumber was mentioned as a fix for crackling audio in Gnome in this post: Initial Feedback on the Community and Distro Itself