Grandstream setting needs to be the 3rd radio button (cannot remember the label) Asterisk needs to be the rfc2833 This is the standard setup for Grandstream phones to work with Asterisk. -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.5.0/325 - Release Date: 4/26/2006