The background: trying out direct peer-to-peer SIP between a Grandstream BT100 and a Sipura SPA-3000 with its FXO port connected to a PSTN line. I found initially that the Sipura was very unreliable at detecting the digits dialled by the Grandstream. I have had all my GS phones set to DTMF=SIP-INFO. I found that by changing to RFC2833, the Sipura would then detect digits reliably. I'm inclined to switch to RFC2833 for all my phones. My question: what are the pros and cons of SIP-INFO vs RFC2833? Why would I choose one over the other, if both are available options? Particularly in the context of SIP phones with an Asterisk server. Cheers Tony -- Tony Mountifield Work: tony@softins.co.uk - http://www.softins.co.uk Play: tony@mountifield.org - http://tony.mountifield.org