Yealink phones won't register, softphones, grandstream and linksys will


I have a curious problem: on a new installation, I can register softphones, linksys, grandstream phones, but no yealinks. The yealink phones DO work on a local asterisk/freepbx and a different remote server that I tested them with, but when registration fails when they try to register on this PBX. installation details:

centos 6.2 / 32bit

trunks and routes for in-and outbound traffic are working, the only thing I cannot get to work is the Yealink phones.
we are not using outbound proxy, and I have set display, username, authentication name all to the same value to make sure it is correct. the Codecs enabled on the phone are PCMU PCMA G722 and G729; on the server we have ulaw/alaw set.

Please let me know where I could start looking to fix this, because I am puzzled

I just brought a grandstream phone (that was registering fine from the office it was connected in before) into the office wiht the Yealink phones, and it won’t connect either.
I am puzzled as to what it could be. From within this office, I can connect to other SIP providers, but not this server. It is connected via a USB 3G modem. as I said, I have 7 phones connected on that network to other SIP providers, so bandwith or NAT is not the problem…
any ideas anyone?

Please try setting NAT to yes in sip.conf

Ignore TimTur’s advice. Do not ever edit sip.conf

Have you configured NAT settings correct in the sip settings module?


thanks I will check this out now. It seems as if they are correct, and I connect from other locations, but I do need to doublecheck things, as this asterisk is hosted on a virtual server - Maybe I should have mentioned this before, but I didn think of it before.