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Switched out u6620 changed u6201 checked traces for c6620/21 and r6622 even changed out c6620/21. Still no luck but i did notice that u6880 and sorrounding resistors had water damage as well.
U6880 is for microphone.
I suppose you still have some resistors, or small coils affected by corrosion in that area.
Various components related with tip detection can trick the audio codec.
Also corroded trace could be...
Peel out the black sponge near BIL connector and clean the board there.