Part 2: Also, there is a gold contact on the top of the headphone jack. There is a spring contact on the display assembly that contacts this - I had to bend my spring down a bit. If this contact is not good the symptom is you won't really be able to turn the headphone volume down low (it stays pretty loud), and you'll get a LOUD click when moving off minimum volume. Also, if you try the phone before fully assembling it keep in mind the "home" button won't work until the display is fully seated into the case.

My mute/silent switch went bad. I obtained an assembly that included the metal bracket assembly for the mute switch. Here are some issues I ran into and I hope it helps someone out. This repair takes a while - plan on 2 hours or more! I did all my work in a cookie sheet with white paper on the bottom for contrast. It saved me from losing 1-2 screws. Magnetize your screwdriver. My flex cable needed a lot of careful bending to fit the contours needed to route within the phone. I forgot to fold the actual connector up before inserting the logic board, which meant it was hiding under the board, and I didn't notice until I had fully installed the board. This is easy to do on a new flex assembly because the connector want's to lie flat! On reassembly, I had success putting the mute button on the switch, then installing that combination first. Then the volume up/down, then the headphone jack. I placed small plastic shims on the case side and internal side of the headphone jack - for insulation. Part 1