I can't hear the other person when calling on my Lumia 950 XL Dual SIM.

[Windows Central Question]

I just bought a new Lumia 950 XL two days ago, and I'm having this weird issue. When someone calls me or whenever I call someone, I can't hear what he's saying, while they can hear what I say. And it's not just me. My friend is having the same issue on his Lumia 950 XL.

So can anyone help me here? is there a solution for this issue or should I just take it to warranty?