liyochen1

Hi everyone, like many others, I have my new 8400 recently. I like everything about this unit. However, my friend told me that when I talking through BT, he could hear a low constand buzzing noice. I had U310BT before 8400, and I dont think it has this problem. When I replaced the unit, I left the mic along, as they seemed to be compatible. First I thought was the mic that is causing the promble, so I replaced it and nothing happens. Does anyone has the same problem? Is there any way to fix it?