New EarPods not working correctly with old iPhone

Hi, someone gifted me their EarPods. I tried them on my iPhone 4s running on iOS 7.0.4, but to my disappointment only the left side is audible for all audio from music to Siri. The right side is mute, not even faint sound on full volume. All other functions of EarPods like 'volume change' and mike are functioning properly. But then I tried them on my Lenovo Laptop, and they worked absolutely fine! Both sides were equally audible and loud. I tried them again on my iPhone 4s, but the problem occurred again! Other earphones work fine with this iPhone. Now I know that neither EarPods neither iPhone's jack is damaged (or clogged), it is not a software problem, and also compatible with iPhone 4s as claimed by Apple. I have now run out of possible solutions. Please Help me out. Thanks in advance. (I live in India, where there are no Apple Stores, so please don't recommend me to get them replaced)