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this problem started suddenly
went from mic being too sensitive while phone speaker is on to not warepicking up normal voice
is there some setting? corrupted app? hardware seems ok because
mic works fine with speaker off
Reset all settings. If this does not work, backup your phone and restore it.
tried reset, then a restore and even vacuumed the mic and it still won't work while the speaker is activated
use of earphones uses mic normally
is there some echo cancellation circuitry that could have failed?
no
i am trying to clean the oriface and that has helped, so i think this is a simple mechanical problem
thanks to all for advice

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