Methods and apparatus are provided fox defending against telephone-based robotic attacks. An interactive voice response method is provided for presenting a menu having one or more menu options to a caller associated with a call. The method comprises the steps of obtaining a script to present to the caller, the script including the one or more menu options; combining at least one of the one or more menu options with a background audio signal, wherein the background audio signal is selected based on a context of the call; and presenting the combination of the at least one of the one or more menu options and the background audio signal to the caller. The context of the call includes comprises one or more of an identity of a called party associated with the call and a time period of the call. The background audio signal can optionally be obtained from a library of background signals.