Default [Q] Echo using Aux-In

I connect my Note 3 to my car's Aux-In using a standard Aux-In cable. When speaking on the phone, I hear the person I'm speaking to perfectly clear through my car's speakers. However, they hear an echo in my voice, which lessens if I turn down the volume. I understand this to be an issue with noise cancellation. However, I'm a little baffled that with my Note 2 (and previously HTC One, Note 1), using exactly the same cable and in the same car, I didn't have this issue. Are there any software solutions (app or settings) - I am rooted and using Stock Touchwiz 4.4.2. Alternatively, can someone recommend a cable that would work without this echo issue.

Thanks!