UkEveryone face the same regardless you replace the earpiece hardware. Its just the issue with the earpiece speaker position which gets blocked with dust very easily for which the sound from the speaker doesn't come out clearly. Its a designing error for which we all are suffering.
I have asus zenfone max pro m2 and is my 2nd phone from asus family.
But this time it's earpiece audio quality is really bad, have been replaced it's earpiece 2 times (during warranty period, as in max pr M2 earpiece is connected with main screen, so to change earpiece whole screen should also be replaced, which will cost around 10k) but still facing same issue.
Let me know by commenting if you are also facing similar issue and let's make asus realise and make them to release an update for this issue asap.
Asus zenfone max pro M2 : earpiece volume issue