45 minutos - 1 hora
One day I was using my iPhone 4 and all of a sudden I noticed that the bottom mic (not the noise cancelling one) was not working as I was talking to someone. After reading numerous forums and websites, I determined that the mic has blown out, and it seems to be a common thing with some first manufactured iPhone 4. I took it to the apple store and unfortunately it was way out of warranty (i didn't have apple care either), and the only way to fix it is to get a replacement, which they were going to charge me $150 for it. I then found out all I had to do is change the mic and it was just part of the dock connector assembly. All I had to do is replace that and good to go.
Fairly simple following the guide to replace the dock connector. Just had to make sure to not accidentally rip a ribbon cable or two. I found the parts to remove the battery and the logic board unnecessary. Disconnecting the battery is still a must to do. After I removed the old dock connector, I found that the bottom where the solder points are was pretty dark as if it was burned.
be very careful and use the tools described, especially easy to use tweezers