iPhone 11 Phone Receiver Sound Issue - Crackling Sound & diagnostic tests failure

For some time I can hear a crackling sound in the iPhone 11 receiver. This is not the first time it has happened with me, the issue keeps coming back after several months. I purchased the iPhone 11 in Oct 2019 and first encounter the issue in Jun 2020. The iPhone was in warranty and it was replaced FOC by Apple. Shortly thereafter in Oct 2020 I again witness the same problem. Apple Service Centre suggested screen replacement since diagnostic tests failed for receiver. Somehow the problem was fixed by attendant by cleaning the mesh with vacuum cleaner (claimed as not in front of me), though I don't know why diagnostic tests failed earlier but were all ok thereafter. Now again I am encountering this problem since couple of weeks. I visited Apple Service Centre and after Diagnostic Tests they advised me to replace the phone screen. The phone is almost new with no scratches and damages to body and I don't understand why this issue keeps appearing. I did request the Apple Service Centre to escalate my issue at both previous meetings in Jun 2020 and Oct 2020 but they did not give any importance to it. They don't want to find the root cause and instead just want to suggest an option of screen change which is an expensive affair and there is no assurance that the same issue will not reappear. The attitude and response of support staff is very scripted.

Now I am on verge of making a hard decision if I should continue with Apple iPhone or must I change to other equally good models from competition.

Oh by the way same issue came up in iPhone 6 and I paid for the screen replacement before I bought iPhone 11. Wont be doing same mistake till Apple help me find the root cause of my problem. I did offer them to take my phone for investigation, if that helps.