@frailtyy: The Clara/Forma/Libra lineup is subject to potentially weird and random (-ish) kernel crashes (that the Libra 2 may inherit: surprise!
).
It's the first time I've heard of it happening during sleep, though. A verbose debug log might help (but it probably won't). I've been unable to pull out anything usefull (or, well, at all) out of my Forma when it crashes (I fear it'd require live serial access at the time).