i had a similar problem, after dismissing a viewController, the contentOffset from my tableView was changed to (0, -64).
my solution was a little weird, i tried all the other answers but had no success, the only thing that fixed my problem was to switch the tableView position in the controls tree of the .xib
it was the first control in the parent View like this:

I moved the tableView right after the ImageView and it worked:

it seems that putting the table view in the first position was causing the trouble, and moving the table view to another position fixed the problem.
P.D. I'm not using autoLayout neither storyboards
hope this can help someone!