There is a noise bug in 1.0.8 which occurs when playing low sample rate files using dmix https://bugtrack.alsa-project.org/alsa-bug/view.php?id=958 Note that this bug does not appear in alsa-lib-1.0.8_rc1 and alsa-utils will build fine with rc1 ( bug #79205 ). 1.0.8_rc1 is more stable than 1.0.8 at the moment, at least wrt this bug.
From https://bugtrack.alsa-project.org/alsa-bug/view.php?id=958 : ---------------------------------------------------------------------- tiwai - 03-24-05 21:32 ---------------------------------------------------------------------- Fixed on CVS (pcm_rate.c rev.1.91). Will appear in 1.0.9-rc3 or final. Another triumph for the OSS development model - but shame on Gentoo for prematurely removing the genuinely stable 1.0.8_rc1 ebuild and ignoring this bug.