no audio

I have a 2001 HP pavillion XT919 with windows ME. Serial
number:mx13100236. I used the 2 system recovery disc to
erase than load all original software. The audio was
working fine until I loaded some applications and drivers
from the 3rd disc the application recovery disc. Now i do
not even get the siren at the bottom on the right corner
and the system will not let me update volume or anything
alse with audio. Sometimes it comes up and states no Sound
output device - sound card being used by something else.
Please explain in simplistic terms how to get audio to
work again. Confirm if dpuset.exe is the right audio
driver? 434-244-7812 Bob