ALSA
Introduction to ALSA
The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI functionality to the Linux operating system. The Linux kernel has ALSA support by default, but you need the ALSA Library in order to interface with those kernel modules. Some of the other packages provided by the ALSA developers may be of use to you as well. They are listed below.
You will probably need the ALSA Library, ALSA Utilities, and ALSA OSS packages at minimum. Further information about ALSA and its various packages can be found in the ALSA Wiki.
Project Home Page: http://www.alsa-project.org/
Note on nVidia nForce 430
If you have nVidia HDA audio chips MCP51, MCP55, MCP65, or MCP67, nVidia recommends the hda-intel module for these chips. The ALSA driver code did not include support for these chips until 1.0.14rc1. ALSA-driver-1.0.14rc1 wasn't included in the kernel until the 2.6.20 series. The current stable version of the kernel is 2.6.20. If you have followed the instructions in the stable release of CLFS, release 1.0.0, you likely used the 2.6.17.13 code. You will need to recompile a new kernel using 2.6.20 code. This also applies to Intel ICH9.