Factual error: When Mina is with Dracula within Dr. Seward's room, she is wearing a white nightgown through which, at times, you can see her tiny underwear (more visible when he confesses to be Dracula and she is upset about him having killed Lucy - turning her into a vampire), in a fashion that would not be likely to be worn by women in the late 19th century.
Audio problem: When Dracula and Mina first meet on the street they begin to speak. Dracula's voice has not been dubbed during the first sentence or two. Then in mid stream his voice changes from a high pitched regular rehearsal voice to the heavily accented Romanian voice used throughout the rest of the picture. (00:45:20)