Audio problem: When Martha is talking to everyone on her laptop, we can see her mouth moving from the front view. Yet when the camera cuts behind her, she's still talking but we don't see her mouth move. (00:28:32)
The End of Time: Part Two - S4-E18
Audio problem: During the climax, when the Doctor has Wilf's old service revolver and is alternately pointing it at the Master and Rassilon, there's a cocking sound every time he turns. Not only is the handgun a revolver, so it only needs to be cocked once, the Doctor is only shown actually cocking the gun once, when he first points it at Rassilon. (00:44:10 - 00:45:55)
Chosen answer: No, no information is avalible for the identity of the entity.
Repo_Man