Audio problem: In the first segment young Kari and Agumon come across some soda machines. Kari says "soda I'm thirsty are you?" But in the next shot we see that Kari has her whistle in her mouth. She wouldn't have been able to talk like that with the whistle in her mouth.
Digimon: The Movie (2000)
1 audio problem - chronological order
Directed by: Mamoru Hosoda, Shigeyasu Yamauchi
Starring: David Lodge, Bob Papenbrook, Joshua Seth, Lara Jill Miller
Other mistake: When Tai is typing an e-mail of apology to Sora, he accidentally types "Love Tai" as opposed to "From Tai" which he finds more appropriate. At that moment, Kari walks in, resulting in Tai's embarrassed stumble into the keyboard. We then see a highlighted "From Tai" change into "Love Tai". It is possible that Tai had already changed it before we saw it and then accidentally pushed Ctrl+Z upon Kari's arrival, but this is more than doubtful.
Willis: Is there anything I should know?
Davis: Yeah, I'm the only one who can kiss Kari.
More trivia for Digimon: The Movie
Question: How did the phone booths, the trolley, and the vending machines end up in the digiworld?
Answer: This happened in the TV show. We are never told as to how they got there but in the last episode Gennai asks them if they could return the streetcar to San Francisco for him. So my guess is that people like Gennai left the items there.