I really like my HP ENVY 17 laptop, but the audio really is bad.
I'm a music producer by trade and know sound very well. Comparing the audio via headphones, the Beats Audio hypes up the sound to stupid levels of bass & harsh mid & top end and over compresses the audio.
When I disable (by pressing Fn B) the flat sound is improved and more natural, but when comparing the same music to an iPhone 5s at the same level, the internal sound card headphone output of the HP is really lacking bass & lower mids, and generally isn't a true flat sound.
For a company that prides itself on audio quality, Beats really has lost the plot on this Laptop. It's speakers lack bass end, even when hyped through the Beats EQ, and they also aubs rattle slightly when watching movies or listening to some hiphop.
Very badaudio design. Other than that I great laptop! 
/ Such a shame. Please let us have a flatter more pleasing sound.