I've a Sony Xperia Z smartphone and I recently updated Android from 4.3.x to 4.4.4. Ever since that I'm unable to hear people when making phone calls, except when I enable the free-speech button (where the side-speaker is used).
Applications like Youtube are affected as well.
I already toyed around with sound settings and, after seeing a notification about a headset being connected to the phone (which is not the case), plugging my earphones in and out, without success. For the record: Sound is played through the ear phones the moment they're plugged-in.
I also never saw that notification again. IIRC the notification had the 'Smart Connect' icon, but I'm not sure about it.
Sony support told me to use the repair functionality of their software which does not work (Something something update routine error 2003).
Hope someone can solve this for me.