Having Annex "a" support, gives a lighter computational algorithm of "a". The GW do select that automatically, depending on the platform and the "dsp complexity" chosen, where applicable. Basically, you don't need to worry about it.
Annex "B", is a sophisticated VAD scheme embedded in the codec, that cannot be disabled. don't select g729br8 unless you really need to save bandwidth (not much people like VAD anyway).
I'm not able to access my old voice mail messages all of a sudden. The recording says something like 'the message is currently not available'. This has never happened before in all the years I have been using this system. I have t...