Yes, and other factors too of course. Physical characteristics of the components, size, shape, material composition would affect this as well. I could hear the noise quite well, since the circuit board was fairly flat and made for a good speaker surface. The power supply manufacturers have their own agendas for their designs. Power efficiency, large power output, ability to handle transients (large sudden changes in power demand). They attain these characteristics different ways, so some may have these issues because they used method A, while method B produces a similar result, but with other tradeoffs.