So my iPhone 4 has suffered much physical abuse, and finally whenever I make or receive calls, the person on the other side cannot hear me, and I can only hear tiny scraps of voice from the ear-speaker.

My question is: if I order replacement parts for these two things, will it fix the problem, or is the problem rooted deeper within the hardware?

All help is much appreciated! I really don't want to go back to my old android phone