Shane Hathaway wrote:
I just bought a set of Phoenix Audio Duets for VOIP conferencing. They are USB speakerphones with good echo cancellation. They work fine with the snd_usb_audio module, with one exception: I can't control the microphone and speaker levels. ALSA exposes some controls, but they have no effect, so I have to shout to be heard.
Update: it turns out that the Duet mixer controls work perfectly with alsamixer and amixer. So once I have the card index (3 in my case), all I have to do is this:
amixer -c 3 sset 'PCM',0 100%
Once I did that, the microphone level was very good.
However, mysteriously, the microphone level control in kmix is not working (it does not generate any USB events at all) and neither of the level controls in Ekiga is working. My system is Gentoo, I'm running Linux 2.6.22, and my alsa-lib is version 1.0.15_rc2. I've seen similar behavior on two Ubuntu Dapper boxes. I intend to look into these problems.
So I just thought I'd let everyone know that ALSA is fully compatible with the Duet after all. Both kmix and Ekiga seem to have trouble with the level controls, but at least you can fall back to amixer or alsamixer.
Shane