iPod Touch screen white after replacement.?

After replacing the screen on several iPod touches two of them came up with a white screen. These screens showed up fine when I tested them but went white after placing them in. I have ruled out software and have restored one of the iPods, I have tried to reset it but it will not reset. The iPod will turn off but will not come back to the apple logo screen, instead it stays black and goes into recovery mode. It is not a screen issue because the screens I have seen working. It is also not a connector issue, I have inspected both the connector and jack using a loop and found no issues, as well as having previously seen the screen functioning perfectly. I believe there is an issue with grounding on the spring and that causes it not to reset. If you are familiar with this please help. Thank you.