iPod HELP. iPod ruined my earphones x3 already!!

Hello.

I'm using 8 month old iPod Nano (3rd gen) and here is my story :

After 5 months of using it, the left earphone volume went suddenly very low, so I bought a new pair, the same thing happened after a month, now I bought two weeks ago new ones and today I discovered the same thing - the left headphone volume is VERY low.

And yes, I tested all of them (headphones) with diffrent things, like laptop and PSP.

Can I somehow fix the volume or do anything?

Thanks.