Have a yellow p5 for sale. Purchased not running with 130xxx on the dial. Got car running currently at 146xxx will continue to change as is daily. Car lowered on springs, two blown struts up front (hit a pot hole). Other than that everything else works. Bought car with chrome 17s currently...
But the video he's standing still....not moving so not technically while braking.....he could release brake and use parking brake or even just in park and see if noise is still there. I doubt it's axles just because the fact that they are not really doing much aside from front to back motion.
Strut bearings and strut mount bushings. Mine was doing the exact same thing. I replaced em. Noise gone. Jack the car up get weight off the mounts, then try again. If noise is gone more than likely bushings and bearings for ur struts.