Very specific issue with Cisco SPA504G

This one is making me a little crazy since its so specific.

But I am curious if anyone has seen this before. I have an install with a couple of SPA504G’s and 525G’s. If an outside call comes in to a 504g and is forwarded to another 504g the receiving 504 sees the number of the initial 504.

However if that first 504 forwards to a 525 then ,as is typical, the 525 sees the outside number that called in.

Thank You!

Take a look at trustrpid and sendrpid for the extensions. You can set the default for new extensions in Advanced Settings. Changing the default does not change existing extensions so you will need to change them individually.

You also need to make sure that the phones support and are configured to honor connectedline.