1. The only suggestion I have is to watch the Devices and Printers page in the Windows Control Panel and verify each item that is plugged in registers, then add another item.
For instance, plug in the USB hub and wait until it shows up good, then plug in the generators one at a time, waiting to plug in the next until the previous one loads the driver and is happy.
Once everything is connected and happy, then you should be able to run the software to see and control all of the generators.
2.You might also want to look at your power management options for your USB hub(s). You can find this in your device manager - USB controllers. Make sure the box to turn off USB device to save power is unchecked.
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