If the drives don’t even spin after a disc is put in, it sounds like either firmware, or possibly hardware. Although I can’t see how both drives would fail at the same time (and nothing else in the system would). Unless, your power supply isn’t capable of handling the strain of the additional drive.
You didn’t say, but assuming that the drives don’t recognize other media (CDs, DVDs), then you could try a firmware update.
Or, try unplugging one of the drives to see if the single drive works in its absence.
And when I say “unplug”, I mean from the power supply.
They don’t recognize anything. I thought about the power supply but I’ve had them both in for about 5 months. No problems till now.