Under many conditions auditory input interferes with visual processing, especially early in development. These interference effects are often more pronounced when the auditory input is unfamiliar than when the auditory input is familiar (e.g. human speech, pre-familiarized sounds, etc.). The current study extends this research by examining how auditory input affects 8- and 14-month-olds' performance on individuation tasks. The results of the current study indicate that both unfamiliar sounds and words interfered with infants' performance on an individuation task, with cross-modal interference effects being numerically stronger for unfamiliar sounds. The effects of auditory input on a variety of lexical tasks are discussed.