Change Sound Device without Reboot

i have a raspberry b+ with two sound devices (volumio 1.55)
On each devices (hifibery dac+ and headphone) there are music boxes connected.

change output to Klinke Analog

root@volumio:/etc/modprobe.d# amixer cset numid=1
numid=1,iface=MIXER,name=‘PCM’
; type=INTEGER,access=rw—R–,values=2,min=0,max=215,step=0
: values=176,176
| dBscale-min=-103.50dB,step=0.50dB,mute=1

root@volumio:/etc/modprobe.d# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_dacplus], device 0: HiFiBerry DAC+ HiFi pcm512x-hifi-0 []
Subdevices: 0/1
Subdevice #0: subdevice #0
card 1: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 1: ALSA [bcm2835 ALSA], device 1: bcm2835 ALSA [bcm2835 IEC958/HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0
root@volumio:/etc/modprobe.d#

if a change over the volumio webinterface / playback / Audio Output to sndrpihifiberry i can play music without problems
After change to Audio Output to ALSO there is no music

Why ?