Realtek doesn't detect built-in speakers anymore

[Maria-]

I have a notebook with Windows Vista Home Premium and built-in ADS Instant HDTV PCI speakers. In Realtek HD Audio I wanted to choose another audio speaker and I accidentally 'deleted' it from there, somehow. (I clicked "uitschakelen" which is dutch and I think in english it would be like "set off" or something like that)
My question is, how to get it back? I cannot simply search for other audio hardware with Realtek, surprisingly enough.
System Recovery didn't work, neither did a reinstallation of the speakers in Hardware. I (only) have sound when I connect extern speakers with my computer, so the problem is that only my built-in speakers, probably because I removed them from the list of audio hardware in Realtek, or something like that, cannot be started, nor be found.
I'm not sure if I posted this problem at the right place, so sorry if it had to be Software, but OK.

[RoninBlade]

If you installed the proper driver it should work. You didn't not properly configure your sound properties, if it's realtek you are using go in the properties and select the correct device and the number of channels. Try going to the Control Panel, uninstall software, Uninstall the Realtek software and drivers you will be prompted to restart the computer do this Vista will restart and automatically install the drivers.Your sound should then work.