Hardware :: Intel HDA Sound Not Coming Out Of Speakers Though Driver And Software Work

I have a strange problem with my audio on Linux. Some months ago I bought a new laptop (an Asus M51Vseries (M/B version M51Vr)), and now I want to install Linux on it. However, there are some problems. When I first booted up my newly installed Linux distro, Debian Lenny (kernel 2.6.26-1-686), I had sound when I tried to play movies, mp3s, etc. However, after next boot, the sound had disappeared. Nothing came out of the speakers even though everything had worked before. Nothing had changed in the mixers as far as I can tell, either. So I googled a lot and came about pages telling me I should edit /etc/modprobe.d/alsa-base and passing on a model option. Unfortunately it didn't work. I then put off the project a while, and yesterday I tried installing Linux again. Magically, sound worked again, and after rebooting, it had gone. I am at my wit's end.

When I think about it, I find it strange that sound that HAD worked, should stop working, and then start working again by passing a model=... (I tried several) in alsa-base.According to alsamixer (and yes, all channels are at the highest volume level, NOT muted), the chip is a Realtek ALC663. The Alsa version is 1.0.16.I hope you are able to help me. I really want to get rid of Windows, but I won't accept not having sound.