Guys, rear audio works well with 4k movies. The audio from TV channels or music apps are mostly stereo (2.1) . For the samsung HW-N950 rear speakers to work effectively, try playing 4k Ultra HD movies like TRIPLE FRONTIER on Netflix starting from 3:00 mins to witness the rear speakers in action. Absolute bliss!
Yes! I finally figured out the issue with the rear speakers low volume on the SWA-9000S. The speakers themselves are fine, the issue is the terrible design on the red/black wires that go into the speaker. Firstly, the cords are too thin and have a bad contact with the speaker so there is no fixing this; however, there are some things you can try out.
1) pull the red/black cord as far out as possible from the speaker where it is barely making contact but just enough where it clips. If these wires are in too deep, either the plastic will prevent contact (no volume) or the volume will be too low.
2) bump up the "Rear Level" to +6 and knock down all the other configurations to below 0.
Samsung needs to recognize this terrible design in the cord and make a more robust red/black wired available.