Continuity mistake: After Dave has caught Alvin from off his head and trapped him inside a woollen hat, the removal of the hat causes Dave's hair to get messy and parts of hair have fallen down over his forehead. But in the following shot his hair is neat and brushed back to how it was before. (00:13:15)
Continuity mistake: When Dave catches Alvin from off the top of his head and traps him inside a woollen hat, he quickly places the hat down on the table and holds the rim of the hat down to prevent him from escaping. However, as he is holding it down the position of the rim of the hat and the actual hat (in his hands) differs from shot to shot. (00:13:15)
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)
Visible crew/equipment: When Dave first discovers that the chipmunks can sing, as they perform on the tree stump outside his window for him, after they sing 'Funky Town' there is a shot from outside looking through the window and to the right of Dave (through the window) you can see the long pole of the boom microphone; it is not seen in any other shots. (00:16:55)
Visible crew/equipment: After Dave has retrieved all of his musical equipment and instruments from the rain outside, there is a shot of him wiping his damp keyboard down with a towel. In this shot if you look in the glass door behind Dave, you can see the hands of a crewmember and the long boom microphone that he is holding, reflected in the glass hovering above Dave. (00:18:20)
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)
Deliberate mistake: In the housing block that Dave's house is in, the house numbers do not match - because In one shot of Claire walking past Dave's house, you can see that the house numbers are in the 1500's - one homes number is clearly 1516. However Dave's house number is 1958. However this is a deliberate mistake as the 1958 on Dave's house is a reference to when the Chipmunk fever was born. (00:23:50 - 00:32:35)
Factual error: When Dave hears the message on his voicemail from Claire, telling him that she will be round for dinner at 7 o'clock, he checks the clock and it is 6:30.p.m. However, bright sunlight is pouring through the windows. This film is set around the countdown to Christmas, so at 6:30p.m it should be pitch black outside, or at least slightly dark but definitely not bright sunshine. (00:30:50)
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)
Plot hole: When the chipmunks finally release their first song, there is a montage showing the chipmunks rising musical success. In one shot we see a marquee promoting "The Chipmunks Premiere CD Release", and on it is a picture of the chipmunks in the clothes Dave has made them (note Alvin in his 'A' jumper.) However, Dave doesn't actually make the chipmunks these clothes until further on in the film. (00:41:50)
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)
Answer: No it isn't his voice.