Help! Mybook Studio II doesn't mount under 10.8

Yes, i try with 10.7 as well, i had 3 Mybook Studio, First unit fauthy and claim from warranty, lost all the data. Second unit sometime fine, sometime gone off, that’s why i get the third unit to back up my second unit data. Did a clean format & update firmware for 2nd unit, and now it work fine.

But now the third unit is giving problem, inside got close to 2TB of projects data.

This is the same problem that i facing.

Mybook Stuiod II not Mouting