Is Obama losing his confidence?

Many of my friends and other observers have commented that Obama has lost his confidence. He certainly has not shown that strong, engaging style that seduced us all before his election. But has he lost his confidence?
No doubt there are lots of good reasons to expect him to have done that. But I can only comment on how his style reflects that.
The myriad speeches that he has to deliver, that are not of his own making, are normally delivered from the 'dreaded' tele-prompter. The problem here is that he is now too smooth. He delivers in complete sentences and does not have those engaging pauses that were so natural to him when he was committed to his own election speeches. The impression is that he is aloof; almost speaking down to us. Not wanting to engage.
One interesting example, that shows he can still do it right, was the White House Press dinner, in June, where he ripped into Donald Trump and was outstandingly funny. His style was back to his best. Huge pauses and lots of speaking in 'ideas' as opposed to full sentences. He looked as if he was talking 'with' his audience.
His other huge weakness is his handling of Questions, especially the press briefings. Someone has got to tell him to cut his answers to 30 seconds or less. The more he speaks the less we listen and therefore the less we are impressed.