BG96 unable to start USB interface

I’ve got some BG96 modules here in mPCIe form, which I purchased a few months apart in different orders. The modules from each order are showing some very different behaviour that I’m unable to change/fix.

My main aim is to be able to flash them all with a known FW image to eliminate the differences. But the problem is that for half of the modules I’m not able to connect over USB to my windows PC. Nothing comes up in device manager at all, there’s no sign of life over the USB interface.

Using the UART interface I’m setting full functionality and getting:

Can anyone tell me what I’m missing here?

Unfortunately there’s another big difference between the modules from each shipment… The one’s with the working usb seem to remain always powered on. If I use either the PwrKey, or the power down AT command, the module just reboots and comes back on again.
Any help here would be much appreciated!

In fact , there is no difference between BG96 and BG96 miniPCIE in fw ( sw)side ,

There are only differences in hardware interfaces

if some modules can not boot normally , pls use force download to burn the new fw again or contact your sales

i attached one forcedown load doc for your reference.