Originally Posted by
Samuraid
Or, if the headphone cord is getting stretched or yanked accidentally, that could cause some damage to the wires inside the cord and may result in one of both of the speakers not working.
I think I've gone through 4 pairs of earphones due to this happenning over the past few years now
And it's always been the left earpiece to die first too, since that's the side that usually has the shorter cable so gets yanked on more easily
3 days seems a bit too short for that to happen though, unless you're really rough with them or move about a lot whilst using them
I'd say Samuraid's first explanation is the most likely cause - make sure they're still plugged into the speaker socket properly whenever it happens