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Reply To: How is the best

Well you need a miracle

In the best of the cases g723r53 will give you 11 Kbps so it will be bearly enough to get the 8 channels together on that pipe, 5 channels will connect perfect with this codec, the sixt one is going to cause the other ones to begin sounding bad, and the 6th one may disrupt some of the calls or cause packet loss on your connection.