Secondary Microphone Problem Z5

[N4]

I just bought Z5 and everybody says that they hear my voice is far ..

Done the *#*#7378423#*#* test and it seems that the primary microphone is working, but there is a problem with the secondary microphone where I also hear my voice as far ..

Help ? =/

[Uliwooly]

@N4

Does your phone has a protective case or anything blocking it? 

the second mic it's at the top of the phone, next to the headset jack.