I have been using different variations of the Sansa Clip mp3 players for several years. Sansa explicitly says that of those players that accept a micro SD card, the maximum size of the card is 32GB. However, all the players I have bought will, in fact, accept and address 64GB when these devices are new.
In my experience the lifetime of Sansa players is only a couple of years. The first thing that fails is the clip attachment. Shortly after the clip fails something happens to the the circuitry that recognizes the SD card. I thought the devices lost the ability to see the SD card. I now find that those devices will still recognize a 32GB card after once having been able to recognize a 64GB. In other words, it seems that the high address bit of the circuitry fails in a way that Sansa knows it will happen so they only advertise a 32GB capacity.
Does this seem in any way reasonable?