https://bugs.freedesktop.org/show_bug.cgi?id=85446#c10

does 2.1 really work since pulseaudio probe front device, the softvol create a two channels pcm softvol but 2.1 try to create a 6 channel pcm softvol 


0.170|   0.000) D: [pulseaudio] alsa-util.c: Route conversion PCM
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   Transformation table:
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     0 <- 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     1 <- 1
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     2 <- none
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     3 <- none
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     4 <- none
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:     5 <- 2
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: Its setup is:
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   stream       : PLAYBACK
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   access       : MMAP_INTERLEAVED
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   format       : S16_LE
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   subformat    : STD
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   channels     : 3
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   rate         : 44100
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   exact rate   : 44100 (44100/1)
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   msbits       : 16
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   buffer_size  : 88200
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_size  : 44100
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_time  : 1000000
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   tstamp_mode  : ENABLE
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_step  : 1
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   avail_min    : 87612
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_event : 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   start_threshold  : -1
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   stop_threshold   : 6206523236469964800
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   silence_threshold: 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   silence_size : 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   boundary     : 6206523236469964800
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: Slave: Soft volume PCM
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: Control: PCM Playback Volume
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: min_dB: -51
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: max_dB: 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: resolution: 256
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: Its setup is:
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   stream       : PLAYBACK
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   access       : MMAP_INTERLEAVED
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   format       : S16_LE
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   subformat    : STD
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   channels     : 6
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   rate         : 44100
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   exact rate   : 44100 (44100/1)
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   msbits       : 16
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   buffer_size  : 88200
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_size  : 44100
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_time  : 1000000
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   tstamp_mode  : ENABLE
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_step  : 1
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   avail_min    : 87612
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   period_event : 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   start_threshold  : -1
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   stop_threshold   : 6206523236469964800
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   silence_threshold: 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   silence_size : 0
(   0.170|   0.000) D: [pulseaudio] alsa-util.c:   boundary     : 6206523236469964800
(   0.170|   0.000) D: [pulseaudio] alsa-util.c: Slave: Hardware PCM card 0 'HDA Intel PCH' device 0 subdevice 0