No sound from left speaker

[danilo_giglitto]

System: Windows 10 Home 64-bit
Battery or AC: both
Model: Asus Zenbook UX333FA
Frequency of occurrence: permanent
Reset OS:
Screenshot or video:
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Detailed description：A few months after I bought the laptop, I started to hear either a crackling sound or no sound at all from one of the two speakers (I don't remember which one). After having carried the typical troubleshooting provided by official sources (ASUS and Windows), I contacted Support, which made me sent the laptop to a repair center (my RMA number was: GBB4L20269). The issue was then fixed, but today the problem has reappeared. I have no sound from the left speaker, and an intermittent crackling noise is produced when a play a YouTube video.
Can someone please advise on how to fix this issue?

[Blake_ASUS]

Hello Danilo,
Does headphone have the same issue? or only the built in speaker?
Was there any update or modification before the issue occurred? (may check the windows update history)
Thank you.

[danilo_giglitto]

Headphones experience no issue, the problem appears only with built-in speakers. The only recent update installed has been February 9, 2021-KB4601050 Cumulative Update

[Blake_ASUS]

Hello Danilo,
May you help to record the sound if possible?
And if you enter safe mode, or like tilt the device a bit, does it still have the issue?
Thank you.

[danilo_giglitto]

Hi and sorry for the delay. The issue persists in Safe Mode. The left speaker does not produce any sound at all (even when I tilt the device). Please check the uploaded video as proof.

[Blake_ASUS]

Hello Danilo,
Please kindly send the device to our service center.
Really sorry for the inconvenience caused.
Thank you very much.