Galaxy S6 :: Music Mutes When Notification Comes In?

I never had this problem with my past Nexus phones so I'd think it's a Samsung thing. But when playing music, it will mute for a good 2 seconds or so and then resume after the notification.

This is annoying but becomes even more annoying when you are in a back and forth text exchange, or in a group text. Then the music will mute and you'll hear a loud notification constantly..

How do I disable this "feature". I don't completely recall how it was on my Nexus 5 because it was implemented so perfectly that I didn't even have to think about it and never had a problem.