Continuity mistake: When Dave awakens after being knocked unconscious by the jar in the kitchen, he stands up next to the sink and in the sink there are two coloured flannels hanging over the basin that are spaced far apart. But in close-ups of the sink they are touching. Also when the chipmunks are playing with the blender there is a tin of "Thai Tea" beside the appliances; but this is only there in close-ups. In wide shots the tin is not there. (00:14:10)
Continuity mistake: When Dave hears the chipmunks singing outside on the tree trunk, he goes and opens the window to hear them better. The window to the viewer's right (from outside) has its slatted blinds down - and they are also closed. But after the chipmunks finish singing 'Funky Town', the same blinds aforementioned are now open. (00:16:10)
Continuity mistake: When the chipmunks are cooking toaster waffles, they finally pop out of the toaster and fly all the way across the counter. Simon runs after one but doesn't catch it and it lands in front of him. In shots from the point of view of Dave, Simon is standing with the burnt waffle on the counter in front of him; and around him there are condiment shakers, food packages, utensils and a knife block. However during this scene there is a shot that has the camera behind the counter to show both Dave and Simon. However in these shots none of the aforementioned items surrounding Simon are there apart from the burnt toaster waffle. (00:21:55)
Continuity mistake: When Dave is in the living room, picking up the yellow surfboard, in the wide shot we can see all three chipmunks standing on the small coffee table; and leaning up against the far end of the coffee table is a large painting. But in the close-ups of the chipmunks standing on the edge of the table, talking to Dave, there is nothing leaning against the side of it. Also between wider views and closer shots the items on the table rearrange themselves and change. (00:31:15)
Continuity mistake: When Dave comes back home with the food that he has bought he discovers that the chipmunks have completely cleaned his entire house for his date. When he comes inside and stops to look at how clean the living room is, watch the slatted blind on the door behind him. In the first shot the slats are closed, but when Dave walks into the kitchen the slats are open. (00:31:55)
Continuity mistake: When Dave and Claire are having dinner together, the amount of white wine in Dave's glass is inconsistent during the scene. In the opening shots the glass is almost full, but when he picks it up to drink from it the level is much lower. Then when he puts it back down and the scene continues, the level differs during all the shots of dialogue between the two. (00:32:50)
Continuity mistake: When we see Dave making the shoebox house for the chipmunks and writing a letter to them, Dave pokes five messy airholes in the top of the box. However when he decides against the idea and puts the box up on a high shelf, now you can see that in the lid of the box there are now seven airholes and also the holes looks much neater than before. (00:37:00 - 00:37:55)
Continuity mistake: When Dave is in the supermarket with the chipmunks, the chipmunks are in the trolley. When Dave turns his back, the chipmunks overload the trolley with boxes of toaster waffles. In the following shots during the whole scene with Dave talking to the chipmunks and then discovering that the chipmunks' song is on the radio, the amount of boxes of waffles in the trolley and the boxes' positions change. (00:40:35)
Continuity mistake: When the chipmunks are giving Dave the presents they got him, Theodore had made him a card out of a folded sheet of paper. On the front of the card he has written (and misspelt) "To Dav" - note this handwriting. From when the card is laying on the table to when Dave picks it the writing has changed. When it was on the table the T was crossed and the V was longer than the A. But when Dave picks it up the T is uncrossed and neat and the V is now the same size as the A. (00:45:50)
Continuity mistake: When the chipmunks are giving Dave their gifts to him on Christmas morning, after Dave has opened and read the card that Theodore made him, he puts it back down on the table. In the following shots the position of the card changes from straight to diagonal and back. (00:46:30)
Continuity mistake: When Uncle Ian arrives at Dave's house on Christmas, he comes in with a huge pile of gifts as well as a huge Santa sack full of presents for the chipmunks. When he walks through the door with the sack the door swings to a shut behind him. But in the next shot more people from Jett Records walk through the same door with more gifts - only now the door is wide open for them. (00:47:25)
Continuity mistake: When Ian visits Dave's house on Christmas, bringing over all the gifts and toys for the chipmunks, he hands Dave three large gift-wrapped boxes for them. He then mentions he got Dave a CD and places the wrapped CD on top of the three boxes that Dave is holding. Then when Ian is leaving, between a couple of shots the position of the wrapped CD on the top box differs. (00:48:30)
Continuity mistake: When the chipmunks are performing the song 'Witch Doctor' for the Jett Records premiere, they are performing on top of a giant sealed cauldron which has mist bubbling out from its rim. During the scene the amount of mist that is flowing from the cauldrons rim is not consistent; in one shot the mist might be coming out fast and thickly but in the next it is bubbling out in thin slow wisps. (00:50:50)
Continuity mistake: After the chipmunks have performed 'Witch Doctor' at the Jett Records presentation, everyone starts to applaud and in one shot we see a huge net-load of balloons fall from the ceiling, onto the dance floor (which has been made to look like a huge vinyl record.) However seconds later we hear the DJ to tell everyone to start dancing and there is an overhead shot of everyone moving onto the same dance floor; only now there is not one single balloon in sight and there is no way they could have all disappeared off the dance floor. (00:51:25)
Continuity mistake: When Claire walks over to the signing table that Dave and the chipmunks are sitting at (after their stage performance), she bends down to take a photo of them and Dave holds his hand up and forms a 'peace' sign with his fingers behind the chipmunks. But in the following reverse shot the chipmunks cannot be seen in front of the peace sign, when they should be visible. (00:52:10)
Continuity mistake: In the scene inside the house that Uncle Ian gave the chipmunks, Alvin has foam darts on three air-pump launchers. He fires all three of the foam darts from the launchers; and we see him standing on the table with the three launchers and the three attached air-pumps, nothing else. But in the next shot suddenly all three of the launchers have a foam dart readily attached to them! And in addition a large pile of foam darts has appeared on the table, behind Alvin. (01:00:30)
Continuity mistake: Inside the house that Uncle Ian gave the chipmunks, the chipmunks are all playing with the new toys they have received. Simon and Theodore are on a trampoline and Alvin is playing around with foam darts. In one shot we see four foam darts shoot across the room in succession - however there are only three dart launchers. (01:00:30)
Continuity mistake: When the chipmunks start practicing for the first time with Ian, Ian gives Simon "cooler" glasses that he should use it from now on. However, in their tour shots he's still using his old glasses. Much later in the movie he is also seen rummaging through a desk cabinet for his his old glasses which he found to be already bent. (01:01:50)
Continuity mistake: In the scene where the chipmunks are on the set of the Crunchy Nibbles advert, they are each standing in front of a bowl of the nibbles. But they are completely knackered, and Theodore falls forward into his bowl, causing nibbles to spill all over the table. However in the following shots the amount of nibbles around the bowl on the table is inconsistent. (01:03:20)
Continuity mistake: When the chipmunks are in the recording studio they are too exhausted to sing their song, so Ian comes in with plastic cups of coffee for them. Above the chipmunks heads is a large silver microphone - during this whole scene the microphone alternates from being just above their heads to being much further above their heads. (01:04:00)
Answer: No it isn't his voice.