Audio problem: When the thief with one arm tells his other two buddies to "check this out" the shot switches to the right side of him. In that shot you can see this guy say "check this out" again.
Audio problem: While Sean and Whitney are tossing the football at the lake edge, at one point we hear Whitney catch the ball offscreen while the camera is on Sean. The camera then cuts back to Whitney and he catches the ball on screen. (00:03:20)
Audio problem: At the hospital Clark and Jason talk about Clark possibly being on steroids. Watching Jason's mouth reveals he actually says "and a college career." before he says it out loud a few seconds later.
Audio problem: After Clark's parents come home, after their anniversary dinner, Jonathan and Clark go to see Earl in the hospital. As the Doctor says "It looks like he's got some sort of mineral poisoning, but its not from any mineral I've seen before." For the first few words of that line her mouth does not match up to what is being said but the dialogue, and her mouth slowly come together at the end of the line.
Audio problem: The CD playing in Lex's car is heard at exactly the same volume and quality from outside the car when Lex has his windows up and when he rolls one down. (00:10:20)
Audio problem: Towards the end of Lex telling Clark about his car, that it was stolen and returned, Lex says "Often that can be the test of a true friendship." After Lex's line the camera switches to show a reaction shot of Clark. In that shot, just before it switches back to Lex, you see Lex's mouth move as if he is saying something but there are no words heard.
Audio problem: While talking about Tina Greer's suicide after Chloe says "lit a match" you can hear Pete say "okay" but you see his mouth doesn't move with the word.
Audio problem: When Whitney is tearing up the bathroom, he throws the door and we don't hear it land. I saw this on the DVD, so it was not a transmission problem.
Audio problem: When Jimmy is in the 1940s Talon we can hear the sound of a saxophone in the number before Lois arrives. Nevertheless, as we can see on the stage, there are only three instrument: a drum, a piano, and a bass. (00:52:00)
Exodus (2) - S2-E23
Audio problem: At the wedding, after Jonathon gives Lex the compass, in a side shot we hear Jonathon say a line, yet his mouth is completely out of sync.
Audio problem: After he breaks the methane valve, Earl runs to the security camera and whispers, "You see what you made me do?" His whisper is heard at the proper volume by the Luthors watching the camera, but the speakerphone is on the desk ten feet behind Earl, making this impossible. Most surveillance cameras don't have microphones. (00:28:55)
Audio problem: After Perry explains that the information he has on Lionel is with "multiple attorneys with 'in the event of my death' instructions" Perry tells Lex that the information is "all yours". As he says "all yours" the camera is behind and you can see Perry's mouth say "I just want one thing." but you don't hear Perry actually speak the line until the camera has switched and is facing Perry.
Audio problem: After the DCA shows Clark and Jonathan the metallic key, Clark says, "We need to think about mom," but his lips are not moving.
Audio problem: In the scene where Jason and Isabelle/Lana are talking and he is about to burn the book with the lighter, she quickly grabs the book with her magic. Isabelle then says some sort of spell flinging Jason against the wall to the right. In the shot where you see him thrown against the wall, Isabelle has already said the spell, but you can see her mouth moving saying the same thing (though nothing is heard).
Audio problem: After Clark tells Lex why he didn't tell him that Lex's father killed his parents Clark finishes his line by saying "...I couldn't live with that." The camera jumps to Clark's right and you can see he says "I couldn't live with that" again only no sound is heard.
Audio problem: Lana pours Lex a cup of chamomile tea from a Thermos, however the cap is still on the Thermos, despite the sound of liquid being poured. When Lana moves the Thermos, the red dot on top of the plastic cap can be seen.
Audio problem: When Lex gets outside and makes a run for the gate you hear the sound of Lex running on a gravel or small stone covered walkway. However, several time we are shown his feet and he is actually running on a regular concrete walkway.
Skinwalker - S2-E10
Audio problem: In the barn, as Kyla and Clark talk about Skinwalkers, Clark says "like the legend of Naman is just a story?". When the shot switches to Kyla you can see Clark is talking but no dialogue is heard from him.
Audio problem: While Clark says "next time I could hurt you or mom." the camera is behind him. As he says "you or mom" his head is turned so that you can see his lips do not match the words being said.
Answer: The kryptonite only creates mutations when it reacts with the environment and an individual. Remember, the FDA and several environmental groups did check out Smallville after the meteor shower, but found no danger in the rocks. Obviously they're not always emitting mutating rays, or all the flora and fauna of the surrounding area would be horribly mutated.
Phoenix