My Aria Echoes when I talk over the phone!!

My aria echoes when I'm talking over the phone to someone.. I'm hearing myself during the call.. This is very annoying.. Its just been a week since I bought my phone and it has started giving me problems.

This doesn't happen when the "In-call volume" is set to maximum and this problem is prominent when the volume is at half way.

Is anyone facing this problem? Is this a software or a hardware issue?.. one of my friend also faced the same problem.. he realized the problem only after I told him about my issue.

How is it for you guys?.. especially when the volume is at half way..

I'm breaking my head for this problem! I'm just hoping someone should find a fix for this!!

it happened with me with a lot of phones..i think this is more to be with the carrier than the phone itself and is usually self limiting..after a while it doesn't happen, but u need to check ur sim with another phone to make sure it isn't about ur phone, if so u might  need to exchange it..