Same issue, same system (Dell XPS13 DE HAswell - 14.04)
I'm using headphones that have a mic in them, not Del, just a random model
I have noticed that when I go into sound settings, I have 3 inputs, Headset Microphone, Microphone, Internal Microphone.
When I have Microphone selected, the hissing goes away, but so does all the other sound on the unmuted system
Same issue, same system (Dell XPS13 DE HAswell - 14.04)
I'm using headphones that have a mic in them, not Del, just a random model
I have noticed that when I go into sound settings, I have 3 inputs, Headset Microphone, Microphone, Internal Microphone.
When I have Microphone selected, the hissing goes away, but so does all the other sound on the unmuted system