add another one to the list... i have this same problem described down to a tee as above. i have done everything suggested in this thread and the forums, including
-NAND
-Revive Bad Blocks
-Re-Format
-Charge Backpack Overnight
-Slightly Bend Pins
-Updated / Downgraded Firmware, trying all the above steps with various USB2.0 firmware versions
..no dice. i think it must be a problem with the brain, because i can sync and get into the backpack with no problems. it started having the symptoms 1 time randomly. then, about 2 weeks later, it did it again... then a few days later again, then daily, now every time i try to turn it on... nothing, only thing that happens is the backlight comes on!!
now at this point, i can rarely ever get into the diag menu. if i force shutdown with UP+PLAY and 1+5+PLAY about 20 times in a row, sometimes the diag menu comes up, then it locks up within 15-20 secs. i got it to NAND and revive bad blocks completely 1 time, it played an MP3 for about 1 min, then locked right back up and its back to square 1...
i think the neuros folks should really start to consider this as a defect, as it appears that most of us got the units around the same time. i just got a hold of support today and they told me to send it back
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