“Sound travels at 761 MPH plus however fast you’re walking with these speakers”
Sound always travels at the same speed (for a given density of what it’s going through), and your personal velocity does not change that. It’s why the Doppler shift occurs - the sound waves are actually producing a shorter/longer wavelength due to motion.
I bought four of these the last time they were offered and two would not charge.
likewise, bought 2 last time and one would not hold charge at all
Sorry for the problems. Not sure which item you’re talking about but do contact either the manufacturer or email@example.com for assistance (depending on the warranty).
Is only one needed or do I need two? How many can plug into one iPhone? Can they plug into each other to create a wall of sound?