iPhone 4 (GSM) Audio IC

**Dater** · 21-07-2013, 04:01 AM

Hello there!

This is my first REAL post. Here is my question:

I have a customer with the following problem. He can't be heard during a conversation. But if you test the microphone with the voice memo app. It works flawlessly. Also if during call you go on speaker mode people still cant her him, but the secondary microphone is fine (tested with a short video recording).

I believe this problem is widely known as "Audio IC" problem, where there are some cold joints because the iPhone fell down on the ground just one too many times

When I start a call I cant hear anything from the broken iPhone. But when I apply some pressure at the the Audio IC then suddenly you can hear everything... so I used my newly bought SMD rework station... set the temperature.. heated the Audio IC for about 10 seconds... applied pressure like i did before and let it cool down for about 30 seconds...
I tried that with the following temperatures:
225°C after cooling down no change.. still didnt work... only when I apply pressure it works...
250°C after cooling down it still works... then gently knocked the logic board against the table for a few times to simulate daily use... after that didnt work again.
275°C after cooling down still worked... but then not...better stop now...

When I apply pressure again it works...

So I put some plastic card on the chip so it will constantly apply pressure on the Audio IC. Because I don't dare to apply higher heat... (I think i read it here or in another forum?)

Anyone has any experience with this? Hamesjerss for example?

PS: It's my birthday today. So please be nice