Hi Philippe,
Btw, TString only works with h323, SString also with SIP.
This sends a message which you can process with an extneral control system. If you want to
build something your self an arduino or raspberry pi should do the trick as well.
You would need to grep the feedback on the remote codec and generate a new command to
display it via xcommand message.
I am not aware if you could handle that just on the codec, you can run some local scripts on the codec,
but I never tried if its possible to handle xfeedbacks locally on the cocec.
Maybe the integrators forum could be a good place to ask as well:
http://developer.cisco.com/web/telepresence-developer/forum/-/message_boards/category/5354383
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