Jochen Sch?fer wrote: > Is there any documentation about all these controls and what they mean? The first page of the datasheet might help: http://www.analog.com/UploadedFiles/Data_Sheets/206585810AD1980_0.pdf > numid=2,iface=MIXER,name='Master Surround Playback Volume' > numid=10,iface=MIXER,name='Master Playback Volume' > numid=8,iface=MIXER,name='Surround Playback Volume' > numid=4,iface=MIXER,name='Center Playback Volume' > numid=6,iface=MIXER,name='LFE Playback Volume' Volumes for the various output jacks. The Master Volume doesn't control anything but the front jack for historical reasons. Many mainboards exchange the front and surround jacks because only the latter has an headphone amplifier. > numid=25,iface=MIXER,name='PCM Playback Volume' Volume of sound data from the computer. > numid=19,iface=MIXER,name='Line Playback Volume' > numid=21,iface=MIXER,name='CD Playback Volume' > numid=16,iface=MIXER,name='Mic Playback Volume' > numid=14,iface=MIXER,name='Phone Playback Volume' > numid=23,iface=MIXER,name='Aux Playback Volume' How much of the inputs is routed to the output. > numid=17,iface=MIXER,name='Mic Boost (+20dB)' > numid=29,iface=MIXER,name='Mic Select' > numid=26,iface=MIXER,name='Capture Source' > numid=27,iface=MIXER,name='Capture Switch' > numid=28,iface=MIXER,name='Capture Volume' For capturing. > numid=30,iface=MIXER,name='IEC958 Playback Con Mask' > numid=31,iface=MIXER,name='IEC958 Playback Pro Mask' > numid=34,iface=MIXER,name='IEC958 Playback AC97-SPSA' > numid=32,iface=MIXER,name='IEC958 Playback Default' > numid=35,iface=MIXER,name='IEC958 Playback Source' > numid=33,iface=MIXER,name='IEC958 Playback Switch' > numid=45,iface=MIXER,name='IEC958 Output Switch' S/P-DIF controls. > numid=39,iface=MIXER,name='Surround Jack as Input' > numid=40,iface=MIXER,name='Center/LFE Jack as Input' These control whether the other jacks are output or input ports. (alsamixer will display them as 'mute' controls). > numid=36,iface=MIXER,name='Exchange Front/Surround' > numid=37,iface=MIXER,name='Spread Front to Surround and Center/LFE' > numid=38,iface=MIXER,name='Downmix' Various routing options to make determining which channel goes to which output jack more confusing. ;-) > numid=46,iface=MIXER,name='VIA DXS Playback Volume' > numid=47,iface=MIXER,name='VIA DXS Playback Volume',index=1 > numid=48,iface=MIXER,name='VIA DXS Playback Volume',index=2 > numid=49,iface=MIXER,name='VIA DXS Playback Volume',index=3 The VIA AC'97 controller can do hardware mixing with four streams; these are separate volumes for each of them. (The "PCM Playback Volume" of the codec is for all streams mixed together.) HTH Clemens