I am currently working on an upgrade to one of my clients. They have 1 (one) Mitel5000 6.0.11.98, and are using multiple IP phones over 4 separate static IP networks on their site. I have all of the IP phones 5320 and 5330's NAT'ing to the system. All of them work fine. I installed 3 5610 SIP dect cordlesses at one of the locations. I get the "full moon" and such. BUT, during 21 separate test calls only 1 of them had two way audio (call #18).
My first question is: Does SIP require different ports opened to pass audio, other than the ports required for normal IP phones? If so what are they?
My second question is: With DMZ set at the firewall where the system resides, the audio is still one way, unless we change the ip scheme at the sip dect location. (i.e. the system ip location scheme is 192.168.1.XXX and so is the location of the SIP dect; to make the SIP dect phones work, we have to change the location where they sit to 192.168.2.XXX). Is there any other work around for this?
Please advise?
Thanks in advance!!