As the film traces the history of pop music in America during the 20th century, all music featured is from US musicians/artists... except the Sex Pistols, who are a UK band.
The German Soldier who shoots the pianist is wearing an American Helmet with a Swastika painted on the front (which was not the case in any German forces during the war). Also, his weapon is obviously a semi-automatic rifle but he fires it full-automatic as though it were a sub-machine gun.
Zalmie and his mother flee the czar in Russia but when they are in the US they speak what some people mistakenly assume is German. They're actually speaking Yiddish, which is similar to German and was the language spoken by Jews in Russia at the time.
When Pete is playing "Night Moves" in the recording studio, his fingers are moving up on the piano although the notes in the song can clearly be heard going high to low.
When Tony meets the waitress in Kansas, he asks her a number of questions which are references to songs about the state. He asks her, "Is everything up to date here?" which references Rodgers and Hammerstein's song "Kansas City" from the musical "Oklahoma!" However, that song actually concerns the Kansas City in Missouri, as another song from that show indicates.