How to diagnose a sound problem?

Question

Realtek

Given:
ASUS laptop, Windows 10, Realtek HD Audio driver installed.
For some time now, a catastrophic drop in sound quality has been observed on the speakers built into the computer (wheezing, crackling, swallowing frequencies, etc.).
Since I use headphones almost all the time, I put up with it, because I didn’t really bother.
Today the symptoms have worsened. Now the sound on the built-in speakers is not reproduced at all. Instead, regular clicks are heard from them (somewhere a little more than once a second, at regular intervals). The sound is still audible through the headphones, but the problem is that the clicks from the speakers are now constant when any sound is played, even when the headphones are plugged in (HD Audio manager fixes the insertion of headphones into the jack, but if the speakers were turned off before, then now clicks are always heard from them).

All the standard manipulations for reinstalling drivers, resetting settings, etc., of course, have already been done. The question is how it can be fixed, and in which direction to at least dig.
As a solution, I will even take advice on how to get rid of clicks, as they interfere with home ones. There is an option, of course, to turn off the device altogether, but this is the last case, I would like to leave the opportunity to use at least headphones.

I suspect that it is necessary to open and see what physically happened on the motherboard, but there is not enough knowledge and skills for this.

Answer 1

Search Google for service documentation for the laptop, something like - my laptop service manual
According to this document, you can easily disassemble the laptop and physically turn off the speakers, it is very likely that they simply died.