Recently we were challenged to make a TDD/TTY machine work using VoIP. We have a Call Manager on a 100% switched network. We are also using using an 800 series router to provide the VoIP to PSTN connection, with great success for fax, but we ran into problems using the TDD/TTY... we ran into problems even dialing the unit!! (Yes, we tried using a different TDD machine on the line. It failed too.)
We've resigned ourselves to using POTS, but I was curious if anyone else has had similar issues.
Using a standard acoustic coupler with a Cisco 7960,7940, or 7910 IP phones, the TDD/TTY devices should work. Make sure you use G.711 codec only . With other codecs it doesnt work properly . This should help you to make it work.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.