Hello, Since v15, the 'External Agents' which were in use for Call Queues are converted to 'extensions' with 'Ring my extension and my Mobile at the same time' option. In fact, 'External Agents' don't exist anymore in v15. This is a HUGE problem, because External Agents were not routed via the 'Mobile Agent' (v12 and upwards). Having an Extension with the 'Ring my extension and my Mobile at the same time' option, the External Number cannot send DTMF tones. To be precise it can, but they are intercepted by the PBX because it has a built-in Mobile Agent Service. (More about this in the following, section "Mobile Agent Service" (use Ctrl + F) http://www.3cx.com/blog/extension-user- ... ial-codes/) If you used any other method to call the External Number apart from the 'Ring my extension and my Mobile at the same time' option, like using Forwarding Rules or an Inbound Rule to send it directly to another number, then this should work, at least in v14. IT DOES NOT WORK IN V15 ANYMORE! (see my previous post: viewtopic.php/3cx-sends-dtmf-between-extensions-runk-but-between-runk-runk-intercom-44408.html?forum_uri=3cx-sends-dtmf-between-extensions-runk-but-between-runk-runk-intercom&start=&t=44408#p179644 and thanks a lot to NickD_3CX !) Can someone please confirm this and tell me the new concept/design thoughts about this?