Everything in alsamixer looks ok ... although I'm not sure what problems I should be looking for.
Here is the amixer contents:
tux@slitaz:~$ amixer contents
numid=31,iface=CARD,name='Front Headphone Jack'
; type=BOOLEAN,access=r-------,values=1
: values=off
numid=28,iface=CARD,name='Front Mic Jack'
; type=BOOLEAN,access=r-------,values=1
: values=off
numid=27,iface=CARD,name='Internal Mic Phantom Jack'
; type=BOOLEAN,access=r-------,values=1
: values=on
numid=29,iface=CARD,name='Line Jack'
; type=BOOLEAN,access=r-------,values=1
: values=off
numid=30,iface=CARD,name='Line Out Jack'
; type=BOOLEAN,access=r-------,values=1
: values=off
numid=32,iface=CARD,name='Speaker Phantom Jack'
; type=BOOLEAN,access=r-------,values=1
: values=on
numid=26,iface=MIXER,name='Master Playback Switch'
; type=BOOLEAN,access=rw------,values=1
: values=on
numid=25,iface=MIXER,name='Master Playback Volume'
; type=INTEGER,access=rw---R--,values=1,min=0,max=31,step=0
: values=23
| dBscale-min=-46.50dB,step=1.50dB,mute=0
numid=4,iface=MIXER,name='Headphone Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=on,on
numid=3,iface=MIXER,name='Headphone Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=39,step=0
: values=31,31
| dBscale-min=-58.50dB,step=1.50dB,mute=0
numid=2,iface=MIXER,name='PCM Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=on,on
numid=1,iface=MIXER,name='PCM Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=31,step=0
: values=31,31
| dBscale-min=-46.50dB,step=1.50dB,mute=0
numid=23,iface=MIXER,name='Front Mic Boost Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=3,step=0
: values=0,0
| dBscale-min=0.00dB,step=10.00dB,mute=0
numid=12,iface=MIXER,name='Front Mic Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=off,off
numid=11,iface=MIXER,name='Front Mic Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=23,step=0
: values=0,0
| dBscale-min=-34.50dB,step=1.50dB,mute=0
numid=24,iface=MIXER,name='Line Boost Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=3,step=0
: values=0,0
| dBscale-min=0.00dB,step=10.00dB,mute=0
numid=14,iface=MIXER,name='Line Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=off,off
numid=13,iface=MIXER,name='Line Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=23,step=0
: values=0,0
| dBscale-min=-34.50dB,step=1.50dB,mute=0
numid=19,iface=MIXER,name='Capture Switch'
; type=BOOLEAN,access=rw------,values=2
: values=on,on
numid=21,iface=MIXER,name='Capture Switch',index=1
; type=BOOLEAN,access=rw------,values=2
: values=off,off
numid=18,iface=MIXER,name='Capture Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=54,step=0
: values=47,47
| dBscale-min=-58.50dB,step=1.50dB,mute=0
numid=20,iface=MIXER,name='Capture Volume',index=1
; type=INTEGER,access=rw---R--,values=2,min=0,max=54,step=0
: values=0,0
| dBscale-min=-58.50dB,step=1.50dB,mute=0
numid=8,iface=MIXER,name='Loopback Mixing'
; type=ENUMERATED,access=rw------,values=1,items=2
; Item #0 'Disabled'
; Item #1 'Enabled'
: values=0
numid=15,iface=MIXER,name='Auto-Mute Mode'
; type=ENUMERATED,access=rw------,values=1,items=3
; Item #0 'Disabled'
; Item #1 'Speaker Only'
; Item #2 'Line Out+Speaker'
: values=2
numid=7,iface=MIXER,name='Independent HP'
; type=ENUMERATED,access=rw------,values=1,items=2
; Item #0 'Disabled'
; Item #1 'Enabled'
: values=0
numid=16,iface=MIXER,name='Input Source'
; type=ENUMERATED,access=rw------,values=1,items=4
; Item #0 'Internal Mic'
; Item #1 'Front Mic'
; Item #2 'Line'
; Item #3 'Stereo Mix'
: values=0
numid=17,iface=MIXER,name='Input Source',index=1
; type=ENUMERATED,access=rw------,values=1,items=4
; Item #0 'Internal Mic'
; Item #1 'Front Mic'
; Item #2 'Line'
; Item #3 'Stereo Mix'
: values=0
numid=22,iface=MIXER,name='Internal Mic Boost Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=3,step=0
: values=0,0
| dBscale-min=0.00dB,step=10.00dB,mute=0
numid=10,iface=MIXER,name='Internal Mic Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=off,off
numid=9,iface=MIXER,name='Internal Mic Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=23,step=0
: values=0,0
| dBscale-min=-34.50dB,step=1.50dB,mute=0
numid=6,iface=MIXER,name='Speaker Playback Switch'
; type=BOOLEAN,access=rw------,values=2
: values=on,on
numid=5,iface=MIXER,name='Speaker Playback Volume'
; type=INTEGER,access=rw---R--,values=2,min=0,max=39,step=0
: values=39,39
| dBscale-min=-58.50dB,step=1.50dB,mute=0
numid=34,iface=PCM,name='Capture Channel Map'
; type=INTEGER,access=r----R--,values=2,min=0,max=36,step=0
: values=0,0
| container
| chmap-fixed=FL,FR
numid=33,iface=PCM,name='Playback Channel Map'
; type=INTEGER,access=r----R--,values=2,min=0,max=36,step=0
: values=0,0
| container
| chmap-fixed=FL,FR
numid=36,iface=PCM,name='Capture Channel Map',device=2
; type=INTEGER,access=r----R--,values=2,min=0,max=36,step=0
: values=0,0
| container
| chmap-fixed=FL,FR
numid=35,iface=PCM,name='Playback Channel Map',device=2
; type=INTEGER,access=r----R--,values=2,min=0,max=36,step=0
: values=0,0
| container
| chmap-fixed=FL,FR