Greetings all, Does anyone have any pointers on delivering DTMF reliably to an Avaya IP Office system? We've got a reseller that installs these, And it seems to be a crapshoot regarding if DTMF works well on them. Specifically inbound DTMF (Dialing into the IP Office system, And dialing an extension via an auto attendant..etc.). Most of the time, The system will produce a "That option is invalid" as it's misheard the DTMF. Out of about 30 systems currently serviced, I'd say about 18 of them work perfectly with RFC2833 based DTMF. 6-7 of them work perfectly fine after switching to INBAND DTMF. And a handful (The remaining 6ish) of the remaining don't work well with either. Of the above 30 systems, They range in IP Office version from 7.x to the latest (9.x I think). And there seems to be no correlation with software version and if it functions correctly, Or not. When a DTMF change is made, It's always reflected in the IP office SIP trunk configuration, After we found some wording in the IP Office documentation basically stating it follows whatever the other system presents via DTMF. IP connectivity doesn't seem to be the problem here. As all of the non-functional devices have perfect connectivity, And DTMF can be seen in a packet capture at the port the device plugs into. We're providing SIP to all of these systems with an Asterisk box running 12.8.2. The same box is currently serving about 700 customers. User equipment ranging from just about every known IP phone under the sun, The same with ATA's. Many Digium G-series T1 gateways, Cisco call managers... None of which ever have a problem. Hoping someone has some "magic" they can loan me, Or some relevant settings to tweak (On either system). Nick Olsen Sr. Network Engineer Florida High Speed Internet (321) 205-1100 x106