As an addendum to my previous post: wobbly walls, the evidence!
Skip to about 2:20 and onwards to see the wall wobble. My memory was playing me false before - rather than breaking out of Erica's office, Barbara was trying to break IN to the Governor's room (which makes much more sense!)
I was just about the post that scene.
In the last year I can think of at least two scenes where the wall shakes - one where Rita throws Roach against the wall outside the toilets (and you can see the gap between the walls at the corner) and another where someone is thrown against the wall in the corridoor.
The last year was also especially bad for the boom appearing in the shot, there was one short run of episodes somewhere about 620 where there was sometimes 2-3 appearances of the boom per episode.