A while ago the 3.5mm plug of my Etymotic HF5s broke, so I ordered a new plug and also strengthened the (way too thin) cable by putting a sleeve around it. I used heat shrink tubes on either end to strengthen the cable some more and give it a (decidedly DIY looking) finish. It’s been treating me wonderfully well for the past few months, and feels a lot sturdier now than it was before. Plus, it kinda looks cool ;-).