I think you may be suffering from the bent pin syndrome. I am assuming you did the pin header install.
The pressure of the drive may be disturbing the contact and as much of a pain as it will be to sort it, I would suggest that you check the level of the pins on the pin header. There is an explanation here ......
If you stuck the (optional) foam rubber padding on the chip then I would remove it 'cos it's a tight fit physically!
Hope this helps.