"You know you haven't stopped talking since I came here? You must have been vaccinated with a phonograph needle!"

This quote is a funny way of stating that the individual has actually been talking continuously because the speaker got here. The speaker is suggesting that the individual must have been injected with a phonograph needle, which is a device used to tape sound onto a record. This is an amusing method of saying that the person has actually been talking so much that it is as if they have actually been taping their words. The speaker is suggesting that the person has been talking so much that it is almost excessive to bear. The quote is a humorous method of expressing the speaker's frustration with the person's nonstop talking. It is also a way of satirizing the individual for talking so much.