DTMF SETTING FOR 3CX

[tranceaddict]

I have several DTMF options in my phone setup?

What are the correct settings for 3CX. The options are:

RFC2833
Inband DTMF
Send DTMF SIP info

 

[5qg4]

RFC2833

 

[aabbcc]

RFC2833
Inband DTMF
Send DTMF SIP info

Anyone knows what the difference is? Can I select all of them?

 

[leejor]

Have a look at this site for a detailed explanation....http://www.faqs.org/rfcs/rfc2833.html

in a nutshell...You can send the DTMF "In-Band" as audio from one end to the other or the SIP device can decode the tones and then send SIP packets to the far end where the tones are regenerated. In-band has a lot of trouble and in fact may not work at all when you choose to use the low bit rate encoders.