I don't know that I'd blame the SanDisk card... Sounds more widespread than that. I've got the SanDisk 64GB Class 10 myself, though, and I do have the same issue. What I do to get around it when I'm going to shoot video, which is rare, is go into settings and set it to save to the phone, then switch back to saving to the card afterward. I did see in a thread somewhere where someone did that, but it still saved to the card, but in my case, it did save to the phone. One thing that was suggested in the prior person's thread was to try a reset with the card in the phone, to see if it would then switch back and forth successfully, and my phone has already been reset with card in phone, so I don't know if that's what it is or not, but in my case it worked.