Why aren't my Earphones working on one side?

I have a blackberry Q5, AMAZING device!
however, when i use my earphones, sometimes only the left earphone works. I tried all other earphones and they worked perfectly.
However, when i get this problem on this pair of earphones and i try them with other devices, they work perfectly.
So whats the problem?

If other earphones work perfectly, I would hesitate to say it's your device. I would just go with different earphones for your Q5.