I have the exact same problem with the earphones that came with the phone, after 2 months of usage it stops functioning, but only with the bundled earphones the output and the earphone plug work just fine but the (extremely dysfunctional) android software refuses to swap the output signal from the speakers to the earphones output, after licking the plug of my earphones it suddenly did work since my spit coating on the plug closes the gap and facilitates contact, needless to say this is a perfect example of planned obsolescence (google that)
All by all, android was the biggest scam I ever fell for, and now um stuck with completely dysfunctional software.
Android does not even have a browsing function like spotlight on a iOS device.
To this very day there are downloaded files wandering on my phone, completely unfindable and undetectable, somewhere out there in the ocean of stupidity that android is made out of.
This is my first and last android purchase, I'm racing back to mac a.s.a.p.
The only thing that is for "hipsters" is saying that apple is for hipsters, in reality apple simply works and the software stands to reason.