It's a known issue with Samsung PM981 not working well on Hackintoshes. You might think about replacing it with a known supported drive.
As for headphone, I see you're using a patched AppleHDA.kext. What's and where's the source of that kext?
I see it's for an ALC298. Have you tried AppleALC.kext with layout-id 11, known to work on Alienware 17.
You could try all these different layout-id 3, 11, 13, 28, 29, 30, 47, 66, 72, 99
You'll need to restore the vanilla AppleHDA.kext to /S/L/E, repair permissions and rebuild cache