At first, I wasn't sure about the solder balls. Then I realized they are used to anchor the USB and Power Interface pins on the outside of the Headphone to the internal circuit board.

I had to used a soldering iron to remove the solder balls, so that the internal interface circuit board could be removed. I had to also remove solder from the speaker wires to free up the internal circuit board.

The internal circuit board was also attached a MEMS Microphone that appeared to be monitoring the Speaker Chamber of the Headphone, since it was faced in. I had to remove the outside panel with 'R' on it with a Razor Knife to free the MEMS Microphone. Once the MEMS Microphone was freed, the interface circuit board could be pulled out

USB and Power (Charger) Interface

MEMS Microphone

Sound Ports

Speaker Wires

Internal Circuit Board that interface Power and USB to the Headphones