* key not accepted on oubound calls

I have users who have recently tried to dial in to a conference call which requires entering a number that starts with “". The "” does not seem to be sent properly or at all. We additionally tested it by calling her voicemail which also requires the “*” to engage the prompt to enter her password and it does not work either.

I am using FreePBX which is embedded into my Elastix installation. I am not that good with Linux so bear with me and thanks!

Any ideas?

Just a wild guess, but I wonder if it has anything to do with the fact that * plus some number is used for certain Asterisk functions (attended transfer or recording a call)? If you were to go to Feature Code Admin, Core section and disable the In-Call functions that start with * (or change them to some code that doesn’t begin with *) I wonder if that would make any difference?

There are 29 feature codes that begin with “*” … it doesn’t make sense as once you are on the call the * shouldn’t start a feature code, it should just pass the keypress. I’m assuming those feature codes only work when you aren’t on a call. I hope that isn’t the issue…

Does it work with any of the feature codes?



How do you have dtmfmode set? Should be rfc2833 on both the switch and the phone.


dtmf and dtmfmode are both set to rfc2833 on the elastix box and I have Aastra 9133i phones and I only see 2 DTMF related settings:

  1. Under RTP settings the DTMF Method is set to RTP. Other choices are SIP INFO and BOTH

  2. Suppress DTMF playback: disabled

Under this current configuration it doesn’t work. Also, I changed the DTMF mode to ‘auto’ and it didn’t work then either.

I can find no other settings for DTMF. Note: I setup a softphone from outside the company network (other office) and registered it through my voip provider (nexvortex) and was able to get the ‘*’ to pass through properly. So the problem is inside my network and not with nexvortex.

The PBX is outside my firewall and the phones are inside the firewall. Since everything else appears to be working I doubt this is having any impact. I am using a Watchguard x550e which can do very complex packet filtering but I’m not applying proxy filtering to this traffic.