Just had an interesting test. Two of us were in a conference using our phones connected to SPA-2000s. Then a friend dialed in through BroadVoice. Ouch! His voice was loud.
I immediately turned down the volume on my phone but then I could barely hear the other guy on the SPA-2000.
I see that the Conference command has flags for telling Speex about the user being a telephone device and to enable AGC.
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does not appear to have such capabilities.
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Hmmm...it would be nice to be able to adjust the gain on a SIP channel...
--kyler