I had the same problem (that an incoming call's sound was put through both the ear speaker AND the external speaker) BEFORE the latest updates of Google Chrome. But AFTER all updates to Chrome was installed, I have NEVER had any incoming call through the external loudspeaker! All new incoming calls are only heard on the ear speaker, and NOT through the external speaker on my Sony Xperia Z1 Compact. I have done about a hundreds of incoming test calls, with the latest updates of Google Chrome, without ANY problems with calls both heard on both the internal (ear) speaker and the external speaker. You should be VERY careful when you suggest that users of any Sony mobile telephone should NOT update to the latest version of Google Chrome (or other software), since that may make these Sony mobile telephones MORE vulnerable to malicous attacks!
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