I'm curious as to when the responsibility of a manufacturer ends when dealing with emissions and RF testing, part of FCC and CE tests.
I repair TVs as a hobby and as business. I got a TV in from someone which would not power up most of the time. I found the soft-start circuit was stopping the TV starting, so I inhibited that. Now it works fine. But the PFC transformer makes a very audible whining sound, and the PFC bus voltage now measures 328V - when it really should be nearer to 390V. This tells me the PFC is not working (although the TV is fine with the reduced bus voltage) and so the TV probably wouldn't meet its emissions requirements. In this case, would the manufacturer be responsible for this?
Another example, an old Compaq power supply had a very odd "feature". When the 5V output was shorted, it wouldn't switch off. It would melt whatever was attached (including its own cable harness) and in the process make enough EM noise to cause an AM radio within half a metre to lose a station. Given that the 5V shorting is not a default configuration of the PSU, but it could happen, why is it covered in FCC/CE logos?
See, I am designing a power supply which might have an expected lifetime of 50,000-100,000 hours. But it won't last forever, that's pretty difficult to do. At the beginning of its life it would meet the requirements. But as it gets older, electrolytics degrade, ripple incrases, noise increases. Eventually, it won't meet the original requirements.