Headphone jack on mine has died. I mostly listen to music so this was a deal breaker. Luckily my lass has still got her (my old) M8, so I've had to swap for that.
I was going to get a new phone but I honestly couldn't see the point, today's crop aren't much better, and its certainly not worth shelling out £200+ to have more or less the same experience as on a flagship 2014 model. If I'd taken the plunge it would have been Nexus 6P, but the relatively poor headphone output put me off.
On the flipside, she doesn't use the headphones out and she loves the Sony after the M8... silver lining I suppose!