Unable to use DTMF?

[dbarney]

Hello Everyone,

When we call a phone number that requests us to dial an extension, or something along this line, when we press a button on the phone, the recipient phone system does not receive the pressed key.

I spoke with Inphonex, and they said that it is not on there side. We have tried this on a polycom 5xx series phone. Does aynone have any suggestions as to what might be wrong?

Thanks.

 

[tekknow]

Did you ask inphonex what DTMF they support?

There are three types

1) Inband , works only with g711u or G711a
2) out if Band RFC2833 otherwise known as AVT
3) out of Band Info


You need to support the format that Inphonex uses all the way through the chain as I do not know if 3cx translates DTMF

I do not see DTMF options in 3cx so I ASSUME that it passes whatever you send.

 

[dbarney]

From Inphonex:

For outgoing calls, our system will negotiate RFC2833 AVT, SIP info, or Inband,

Now interestingly enough, the client we are testing 3cx with, said about a week later DTMF worked. The 3cx system had no change made, nor was it restarted. Though Inphonex makes no claim to them being the problem.

 

[warever]

Funny, I'm also using InPhonex and DTMF just plain doesn't work. I'm considering telling them to go to hell and refund my "deposit" (which they managed to double-charge). They've been no help whatsoever. 3CX support said I could try upgrading to the latest 6.1 release which supposedly fixes a few DTMF issues. I'm going to try that and see - but at this point, I simply can't use the InPhonex trunks (and am using POTS lines and Vonage lines delivered as POTS going through gateways).

 

[worksighted]

In my experience, the VoIP provider will require you to send DTMF tones either inband or out of band. There is typically a setting available on your phones that tell them to send DTMF tones in band or out of band. You need to make sure this matches what the provider is expecting or you will experience the behavior you are describing.

Mike