Hi Siard,
good to hear that the solution seems to work. I think the proplem is comming from the connector beneath the coverage. I think a small non-conductive part like an anti-static foam or something similar between the connector and the coverage will help to keep the connector in place (even upon shock from falling etc.).
My phone also works fine since I fixed it.
This could also probably help to fix some of the issues related to ghost inputs on the screen and related.
so long
Max