Are you somebody who owns an iPhone 4/4S and has an extremely low earpiece volume, then here is how you should fix it.
I experienced this issue first on my iPhone 4 and then on the 4S a few weeks later.
Basically what you need is a pin. You take that pin and clean the earpiece and you will see a lot of dirt from your ear coming out.
That dirt covers the mesh grill on the earpiece which then obstructs the volume that you get from the earpiece.
But before you do that you need to put your mouth over the earpiece and suck inwards a few times.
This will not do anything but clean the mesh holes and then you take the pin.
But dont put too much pressure as you could risk having a slight mark on the earpiece.
And on the corners of the earpiece you should be most careful as all the dirt will be stuck there, once its in the corners you can blow and it will all be clear.
Then just blow in the earpiece a few times, and youre done!
You will have the same volume as you did when you first bought the phone and not only that, you will also now have a clean earpiece grill.
I will also be making a video tutorial on this, so stay tuned!