Berlingo 2015 Bluetooth problem

Hi, i have the SMEG+IV2 (jukebox, wifi, mirrorlink and so on). The problem is that when i make a call over bluetooth then nobody can hear me. Everything else is working like a charm but no one can hear me when im on call.

Tryed with two different phones. Nexus 5x (android 7.0) and Xperia XA (android 6.0.1)
My unit version is attached with the image.



any advice would be most welcome