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Extra notes

To get recording to work, make sure that the mixer control AD Input Select is set to off (muted).

You might also need to set the Mic +5V bias control to on using something like

$ amixer cset numid=43 on
numid=43,iface=CARD,name='Mic +5V bias'
  ; type=BOOLEAN,access=rw---,values=1
  : values=on

The magic number '43' can be found from the output of amixer controls:

$ amixer controls
numid=43,iface=CARD,name='Mic +5V bias'
numid=42,iface=CARD,name='PCM 0 Output also on Line-In Jack'
numid=3,iface=MIXER,name='Master Mono Playback Switch'

For type CT4700, the one with 2 line-out jacks (green / black), you have to set number `42` control to on for enabling "hw:0,1" output on line1 and "hw:0,0" on _both_ line2 & line1.

Did this in my "/etc/asound.state", setting "value true" (SuSE9.3).

The (KMix) mixer setting "pcm0" (the leftmost) is for "hw:0,0" -> line1; so you can set "pcm0" to "0" for having one output exclusive for one DA-hw: 0,0->2 and 0,1->1

The mixer setting "pcm1" (2. left) sets level of "hw:0,1" -> line1.

I found no way so far to set level for "hw:0,0" output -> line2, is allway 100% (nor "hw:0,1" -> line2, allways 0%).

Only line1 has a onboard speaker-amp, which you can enable by jumper-setting. At line2, you have to use external amp or active speakers, you will not hear more than whisper even with headset.

Using "hw:0,1" for VoIP with internal amp and headphone on line1; and "hw:0,0" with active speaker on line2 works for me.

However, microphone is on "hw:0,0" only.

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Category: ALSA modules