He’s frustrated that people know that he is to blame, and aren’t buying his lies.
I think what's frustrating him even more is that he's doing his job following Obama's directions to the letter, and finding out that a lot of what he's being told to do is unrealistic, boneheaded and frankly embarrassing -- and it's Joe, not O, that has to take the blame for it.
He's not the first henchman to find out the boss is full of crap.
Nailed it.