I have 100% exactly the same problem. I love the button idea.. so I can press functions with gloves on in the cold, BUT NOT IF THE BUTTONS DON'T WORK!!!
I had the origional pebble - the screen went faulty, pebble replace it... ty pebble. I then sold it and got a steel. I bought it unused from ebay, so effectively new. That was december 2015.. It's been working fine for ages... but now the steel buttons are faulty. So yeah, they've lasted 9 months. You would have thought that the buttons, being the unique selling point of the smartwatch, would work for ever more.
I had a casio waterproof watch as a kid.... and the buttons never broke... they still work 3 decades later... so what's the deal?
Please advise pebble. Thank you.