We have a customer using the G726 vocoder. Up until now we have been using fixed entries in sip.conf which specify an allow=g726. That works fine. Now we are moving to using asterisk realtime, and if I set the allow field in the table we are using to g726, asterisk declines the calls with an error which says the vocoder is not supported. if we set that column to ulaw, everything works, but once it goes back to g726 it stops working. This has never been a problem if we use hard coded entries in sip.conf.
Is there some configuration option we are not seeing which has to be enabled?