I am currently investigating an issue I have internally, and have heard someone else having on the Technet forums: http://social.technet.microsoft.com/Forums/en-US/ocsconferencing/thread/f9512694-c298-4951-b6d6-0d240ccd0397
The issue is that when in a communicator conference call, you cannot send DTMF tones to a PSTN participant. The scenario is as follows:
- Communicator call, or communicator conference call is initiated
- User invites a PSTN number to that conference call
- PSTN number requires DTMF tones, whether it is a conference bridge, or an attendant menu, could be various situations
- No DTMF is received by the PSTN number.
So far, I have been able to confirm a couple of things. This happens with CS2010 as well as OCS 2007 R2. Internally we use a Dialogic DMG2120 gateway, and I have confirmed that I do not see DTMF on the gateway’s SIP side from OCS.
I am using this post to hopefully get some partners and customers to try this scenario, and see if they have the same issue. I would find it hard to believe that this is a bug in OCS/CS2010 that Microsoft has not addressed, but I am hoping to find a common configuration among people experiencing this issue so we can maybe narrow it down.
Typically this is a gateway issue, however like I said, I have not seen any DTMF come from OCS to the gateway when in the conference call.
Please respond in the comments with a brief description of your OCS setup and gateway/SIP trunk, and if you experience this issue or not.
It is identified in the above article. AVMCU does not support DTMF Relay. Thanks to the commenter!