No audio in calls with specific audio device

I recently bought a Razer Kraken 7.1 headset which has a USB connector.
It works with all other programs such as Skype, to make phone calls. I can hear people and they can hear me, no problems.

But when I call anyone in Lync 2013, they can hear me, but I can't hear them.

I made sure my headset is set as default, and that Lync actually finds my Audio device, which it does.
When I try to play sound in Audio Device options on the Lync client, it plays them and I can hear them without problem.

But in calls, they can hear me, but I can't hear them.

Now, if I change the device settings to use customized settings, everything stops working, meaning I can't hear them, they can't hear me.

I've tried this on a PC at work which has Lync 2013 on Windows 7 (32bit), and on a PC at home which is running on Windows 8 (64bit), same problem percists.

Please help me :)