I've marked bug 870360 as a duplicate of this one even though the hardware is slightly different. Let me ask both of you (Bayan and Reece): Is there actually a headphone icon on the front (and not a "Line out" icon)? If so we should consider making a kernel quirk that turns these outputs into headphones at the kernel level instead of working around it in PulseAudio.
I've marked bug 870360 as a duplicate of this one even though the hardware is slightly different. Let me ask both of you (Bayan and Reece): Is there actually a headphone icon on the front (and not a "Line out" icon)? If so we should consider making a kernel quirk that turns these outputs into headphones at the kernel level instead of working around it in PulseAudio.