You have specified markup in a VoiceXML document that is semantically incorrect. For example, this can occur if you have referenced a nonexistent audio file without providing an alternative text-to-speech string in an audio markup element. If the audio file welcome.wav is not available, but referenced in the markup element <audio src="welcome.wav"/>, a semantic error occurs.

To ensure that the example error does not occur, define a text string alternative as a backup, like this: <audio src="welcome.wav">Welcome to this service.</audio>. You can avoid other semantic errors by following the guidelines in the Blueworx Voice Response: VoiceXML Programmer's Guide information and the VoiceXML 1.0 Specification.