Chosen Solution
Everything went smooth while replacing the flex cable, however something weird is happening now. When recording a video everything works fine, but when recording a video on Instagram or Dictafone you can only hear a static noise and no sound recorded. Any idea of what the problem might be?
There are two microphones on the lightning flex cable assembly. Perhaps they were damaged in the process of replacing or simply defective to begin with. They are on two small tabs that each mount on either side of the lightning jack. Check the ribbon for damage like scratches, tears or nicks.