Hello Anhph68,
we have Mediatrix 1204 working with 3CX. Outbound and Inbound.
Try this:
On 3CX site:
Add a PSTN device "generic" in 3CX. Do not set a password!!! Set in advanced "Require registration for" = "Do not require". All other setup are default. Port IDs for example 10001,10002,10003,10004.
On Mediatrix 2104:
Use the Mediatrix "Web Interface", much more easier as the MIB.
1)Do in "Sip > Config" the IP of your 3CX Server in the SIP, Outbound and Presence Fields and set all port on 5060. Put in "SIP USER Config" the 4 port IDs of 3CX (ex. 10001,10002,10003,10004)
2) Do in Sip > Authentication REALM: 3CXPHONESYSTEM (the word not the IP), put in user name for example 10001. And do not use a password!!!!!!
3) Now take your "Unit Manager Network" Software and open with the "Unit Manager Client" the unit. You will find there Telefony Attributes set Port "Telephony Attributes" to "no restriction". "Automatic Call" to "Enable" and "Automatic call adress" to a phone numer or digital receptionist number or ring group. This number have to be the same as in inbound rule of this ID, for example 10001. For example: If you set here "Automatic call adress" to 100 and set up the gateway port 10001 in 3Cx "Configure where calls should be routed..." also to "Conect to extension" 100, the the extension 100 will ring!
That is all, looks easy, but we spend a lot of hollidays and weekends to find out. Hope this will help you.
Frank