Histeria said:

Why dont all the Stormtroopers have Temuera Morrison's voice like Bobba?

The canonical reason (I guess EU) is that most of the Stormtroopers are not clones by that point - most are recruits/drafted. Most of the clones have died or retired (given that they age at the double rate).

But if Bobba is still around (and his voice was changed) then the Stormtroopers should still have Jangas voice no?

And is the 'white C3-PO' footage at the Hoth command center available at all?