ices2 performance with alsa input?

Question

ALSA

I'm trying to raise an Internet radio station, or rather a few. On ubuntu 12.04 there is a sound system, there is no video in its eyes (I work remotely via ssh)

lscpi | grep audio
02:00.0 Multimedia audio controller: VIA Technologies Inc. ICE1712 [Envy24] PCI Multi-Channel I/O Controller (rev 02)

I have this alsa-config

pcm.my {
        type dsnoop 
        ipc_key 123456
        slave {                 
                pcm "hw:0"         
                format "S16_LE"  
                rate 44100        
                channels 8
                buffer_size 10000
        }
        bindings {              
                0 0           
                1 1
                2 2
                3 3
                4 4
                5 5
                6 6
                7 7
        }
        slowptr true 
}

pcm.ch1 {
slave.pcm my
ttable 0.0 1
ttable 1.1 1
}

pcm.ch2 {
slave.pcm my
ttable 0.2 1
ttable 1.3 1
}
#и так далее
...

And some configuration files for ices2 with input via alsa(ch1,ch2,ch3,ch4)

<ices>
 <stream>
  <input>
   <module>alsa</module>
   <param name="rate">44100</param>
   <param name="channels">2</param>
   <param name="device">ch1</param>
  </input>
  <encode>
   <quality>4</quality>
   <samplerate>44100</samplerate>
   <channels>2</channels>
  </encode>
 </stream>
</ices>

Already at the launch of two instances of ices2, the load average crawls into sky-high 1.2-2.0, the ether starts to stutter.

top - 16:06:28 up 1 day, 23:40,  2 users,  load average: 1.16, 1.48, 1.21
Tasks:  76 total,   2 running,  74 sleeping,   0 stopped,   0 zombie
Cpu(s):  1.0%us,  1.7%sy,  0.0%ni, 97.2%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:   3956584k total,   566612k used,  3389972k free,    36048k buffers
Swap:  4099068k total,        0k used,  4099068k free,   388704k cached

Tell me how to fight.