Just a guess, since I don't know linux error messages, but it sounds like hardware trouble.

First things first. Open the player and check the cabling. Then remove that second disk and see if it boots OK after that.

If so, plug the second drive back in and see if it magically boots (maybe a loose cable?). If not, unplug the first drive and re-format the second drive using Mike's builder upgrade. If that's successful, let it stresstest a while. If that's OK, then perhaps someone here can give advice on how to do a full surface scan of the drive?

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Tony Fabris