Asking about iPhone speakers "Sound IC"

I have a problem with my iphones' speakers, where the speakers don't put out any sound, and also the microphone doesn't work, since the other side " the person whom am talking to " can't hear my voice. Moreover, I have a problem with the earphone where it doesn't work while it's plugged, I have tried other earphones and still didn’t work. I think the problem is in my iphone itself, and I want to notify you that all these problems go away for few minutes and then it stops functioning again, and that the speaker phone "mode" is always functioning properly where I can hear n the other side hear me when I activate it. I have tried to send it to phone technicians to fix it, but no one was able to, and all of them told me that my problem comes from the "Sound IC", I want to ask if I can buy a new one and where from, thank you very much for your support.