Dell Inspiron 1300 Ubuntu Mic not working

The latest Kubuntu is still shipping with no working Mic input, no problem though as the fix is simple, we just need to pass the right model code to snd-hda-intel kernel module. I'm using a Dell Inspiron 1300, but other laptops also use STAC9200, such as the Dell Inspiron 6400.

Normally we would cat cat /proc/asound/card0/codec#0 and use the SigmaTel chip id: "STAC9200", but in the case of my chip using a name is not supported, so we must use "ref". If you look at the alsa kernel code patch_sigmatel.c you can see it is "ref":

static const char *stac9200_models[STAC_9200_MODELS] =
{
[STAC_REF] = "ref",
};

We can specify the options in either /etc/modules or /etc/modprobe.d/alsa-base

options snd-hda-intel model=ref

Alsa wiki page for more info. One thing I wonder is that why is it called "snd-hda-intel" in the kernel tree and options, but in the output of lsmod it shows up as "snd_hda_intel" why the underscore difference!?