This is a common problem ALWAYS use the most current sip.cfg!
I have just commented on this here:
voip-info.org/wiki/index.php … +430+Notes
If you update the firmware on your polycom phones you need to use the current sip.cfg files.
In order to do this you need to make sure you DOCUMENT all of your sip.cfg changes for your environment. If you dont, you will have problems. Always read the release notes for all firmware before upgrading. NEVER push an upgrade out before testing it.
I am just saying these things because soo many people where having 430 speakerphone / OTHER issues and it was all because they didnt use the latest sip.cfg - if they used the latest cfg files all would have been well, but since they didnt, the 430s did not have the specific setting they needed in order to operate correctly.