Natalie Luca (No. 184) - S4-E12
Audio problem: At the end of the episode when Reddington goes to see Natalie Luca (behind glass), he tells her that the woman she killed at the massage parlour was an associate of his. When Natalie says "She said if I didn't kill him, she would tell Hawthorne where to find us", her lips don't match what she's saying in the reflection of the glass.
Audio problem: After Deputy Lin drops the line "we'll get the results back fast," Sheriff Alex Romero responds with "I'm not sure how much nail clippings are gonna tell us." As he sits down, his mouth movement matches the audio, but when the angle changes, his mouth isn't moving at all. (00:09:55)