I see I am in the minority here but "bad parts" are bad parts. I agree 3 years is a long time but on the other hand this stuff should not break that easy. I know I would be pissed also but I doubt I would trash talk against one supplier. Sadly 95% of the stuff we are all buying today is made in China and it is a bunch of shit. Chris (HEP) put a post up about that a few weeks ago.
If I was the supplier I don't know what I would have done 3 years later. But I see the OP point also.
The sad thing is accepting junk as being OK is just part of the world we live in. I just bought a new recliner about 3 weeks ago from a major company and that recliner broke in 11 days. They exchanged it with zero issues but I still was kind of pissed because I wasted 1/2 a day dealing with it. Between dragging the broken one back to the store, getting the new one home, unboxed, and put together, etc the process ended up wasting 6 hours of my time just because someone used a bad piece of wood to save a company 25 cents? NO QUALITY CONTROL in CHINA - that is one thing for sure.