Dead Freight - S5-E5
Audio problem: The engine's horn sound constantly changes before the train is robbed. And when the train begins to move again, a railroad crossing bell is heard, even though the crossing ahead just has crossbucks.
Say My Name - S5-E7
Audio problem: When Mike says all that left is to leave town, the audio in the over the shoulder shot stops but Mike's mouth keeps moving. (00:41:20)
To'hajiilee - S5-E13
Audio problem: After Hank and Gomez separate Jessie and Walt after he's arrested, Hank tells Gomez that "I'll call the Tribal Police on my way out, let them know we're here." During the middle of this line, the shot cuts to Walt and you can distinctly hear the sound of a microphone picking up the actor breathing on it as he recorded this line in ADR.
Chosen answer: I'm not sure how far you are into the show but he does eventually come up with a way to launder it (wont spoil it for you but rest assured, when he gets a lawyer the show gets much better!) and in the final season he also comes up with a way to give his children his money without the cops or the DA knowing it came from him.
The_Iceman