A digital interface apparatus is provided for use in an analog musical instrument capable of generating an analog audio signal, and is designed for interfacing with an external digital audio apparatus. The metadata corresponding to the metadata access call is fetched when the metadata corresponding to the metadata access call is not contained in a local filesystem cache that has a hierarchical structure corresponding to a hierarchical structure of the remotely located filesystem. At least one of the first roll and the second roll has elongated embossing elements extending substantially in the machine direction and optionally at least one of the first and second rolls has elongated embossing elements extending substantially in the cross-machine direction. The controller provides signals to a switching circuit for controlling switching of electrical power to a load based on the zero-crossing indications. Also provided herein are vectors and host cells comprising those nucleic acid sequences, chimeric polypeptide molecules comprising the polypeptides of the present invention fused to heterologous polypeptide sequences, antibodies which bind to the polypeptides of the present invention and to methods for producing the polypeptides of the present invention. In response, the data messages are automatically modified to identify the secondary network address.