Hi A friend ( after 11.12 , never before ) started noticing that people could not hear him during calls , but a reboot would fix that ( he was not pressing the mute button ) . I told him that i had never seen that problem , nor reports about it . Today , it happened to me , and i also tried the dictate function in swype , or the voice search app, and my phone did not register any sound. I tried also with a bluetooth handsfree , same result . Wired handsfree , idem . only a shutdown (not reboot) can fix it.