[Asterisk-Users] audio levels via sip

[Greg Hill]

On Sat, 18 Dec 2004, Doug Langley wrote:

> I see from reading the mailing list theres a way to set audio levels on
> the zap channels but I'm wondering if there's a way to set audio levels
> on either sip or iax channels.  I'm using some BT-100's and people are
> saying the audio levels are a little low and I would like to bring them
> up a bit.

audio settings are most likely to be done at the device which does the A/D
conversion.. which is why Asterisk allows you to configure it for a zap
channel (x100p etc anyway.. don't know about the TDM cards). But for a
SIP/IAX/H323/etc channel, Asterisk is just something of a gateway or
proxy. The A/D happens in your handset or softphone, so that's where you'd
have to adjust microphone gain. This would be especially true in a
reinvite situation, where the rtp (audio) stream goes directly between the
endpoints -- Asterisk doesn't even get to see the audio packets!

Greg