It works now after using audio/oss instead of snd_ich ! Of course, you need to customize the kernel to remove sound drivers.
$uname -a
FreeBSD mybsd.zsoft.com 9.0-RELEASE-p3 FreeBSD 9.0-RELEASE-p3 #0: Fri Jul 6 23:01:34 CST 2012
sw2wolf@mybsd.zsoft.com:/usr/obj/usr/src/sys/MYKERNEL i386
$cat MYKERNEL | grep snd_
#device snd_es137x # Ensoniq AudioPCI ES137x
#device snd_hda # Intel High Definition Audio
#device snd_ich # Intel, NVidia and other ICH AC'97 Audio
#device snd_uaudio # USB Audio
#device snd_via8233 # VIA VT8233x Audio
$kldstat
Id Refs Address Size Name
1 13 0xc0400000 be759c kernel
2 3 0xc318a000 7a000 osscore.ko
3 1 0xc320c000 6000 oss_cmpci.ko
4 1 0xc32ab000 6000 oss_ich.ko
5 1 0xc3392000 9000 i915.ko
6 1 0xc33aa000 16000 drm.ko
Regards!