steev@equilibrium ~ $ grep alsa /usr/portage/profiles/package.mask 
# mask new alsa release. Until it is fully added and tested
~media-libs/alsa-lib-1.0.14_rc4
~media-plugins/alsa-plugins-1.0.14_rc4
~media-libs/alsa-oss-1.0.14_rc4
~media-sound/alsa-headers-1.0.14_rc4
~media-sound/alsa-driver-1.0.14_rc4
~media-sound/alsa-firmware-1.0.14_rc4
~media-sound/alsa-utils-1.0.14_rc4
~media-sound/alsa-driver-9999
~media-sound/alsa-header-9999
~media-sound/alsa-lib-9999
=media-libs/alsa-lib-1.0.14_rc1-r1
=media-libs/alsa-lib-1.0.14_rc2-r1
=media-libs/alsa-lib-1.0.14_rc3-r1
=media-libs/alsa-lib-1.0.14_rc4-r1