Hi:
Probably a bad motherboard.
The dv6000/dv9000 models had huge issues with the motherboards.
Issues include: Loss of wireless, loss of audio, DVD drive disappears, video quits working.
These things don't happen all at once, but over time.
That is my opinion.
You can search the issue on this forum or in cyberspace, and you will get more hits than you bargained for.