I have decided to install the Realtek driver (realtek-linux-audiopack-4.06a) manually to see if this gets the internal microphone working. The instructions are
Manual install:
Step 1. unzip source code
tar xfvj alsa-driver-1.0.xx.tar.bz2
Step 2. Turn on sound support (soundcore module, default turn on)
Step 3. Complied source code
a. cd alsa-driver-1.0.xx
b. ./configure
c. make
d. make install
e. ./snddevices
Step 4. Edit your /etc/modules.conf or conf.modules depending on the distribution
(Please refer to the attached modules.conf)
snd-xxxx is the card ID.
I encountered a problem at ./configure with alsa-driver-1.0.14-4.06a. The message in the Terminal is:
The file /lib/modules/2.6.33.6-147.2.4.fc13.i686.PAE/source/include/linux/version.h does not exist.
Please install the package with full kernel sources for your distribution
or use --with-kernel=dir option to specify another directory with kernel
sources (default is /lib/modules/2.6.33.6-147.2.4.fc13.i686.PAE/source).

When I have searched for 2.6.33.6-147.2.4.fc13 in the Add/Remove Software, lots of choices appear but none are prefixed with Alsa or Realtek. I'm not sure which one if any to use. Can anyone help me with this driver installation and tell me where to find the correct 2.6.33.6-147.2.4.fc13.i686.PAE?