Hi All, Long time no chat.

We have finally migrated our ISDN10 service over PRI to a SIP Trunk.

I have noticed this morning that the system won't register on the sip trunk, and when I look, it always adds an additional 4 digits in the programming to the user name (0008)

Is this a firmware bug? Also, can receive calls over the SIP via regsitration per user but cant make calls out - just get "Out of order" when dialling out of 8501 - Is this because of the trunk failure or should the system be making calls based on the Registration per user in the table? Which makes me think - how to do specify which terminal is for per user registration.. Oh boy Ive made a mess! ha. I just don't want to rip out the PABX and replace with new handsets yet as we have a lot of handsets (30+)

(Actually worked out the issue with the Extra digits, used handset to program rather than the PCMMC and OK) but still getting reg errors

OK, so I have the trunk now registering but I am not seeing the digits dialled by the end user through the the DID MMC (It picks up the trunk number as the digits dialled)
Any suggestions

OK - Turns out our PBX Trunk provider had an option to turn on "3CX" pass through of DID digits which fixed it all up. So its all working on a DCS500 for sip trunking. Wooo

Your brave running sip on a 500.
I would've made the carrier supply a pri iad.