I have a dv7-6c43cl.
I also have "no sound."
I've tried the suggestions here (uninstalling, reinstalling, reboot, etc ...it'll work for awhile and it will happen again.
I would plug in a headset and ...BOOM....no sound.
Sometimes the speakers would die by simply placing it on mute.
I've had older ...cheaper...HP laptops with zero problems.
Then I decided to upgrade to this pos...yes..pos. It was working great until 6 months later my display went out! Less than a year! Yes...it was covered under warranty; but it was a hassle and disappointment nonetheless.
If HP wants to charge a premium..how about putting in some reliable parts?
It's doubtful that spending more on a laptop is necessarialy any better.
...and now this sound issue is just pissing me off to no end.
If I can't fix this problem soon I'm seriously done buying HP's or recommending friends/family.
And as they say...bad comments about a company is infectious and viral in this age of technology. Everybody and their grannie will be aware of HP's reliability issues.
/end rant.
Very dissatisfied and disappointed owner