This is a quick tip for anyone that has a Sony HDR-AZ1 action camera and bought a high-speed MicroSDHC card (32GB or less) and is disappointed to learn that the camera refuses to record XAVC-S on the card even though it can handle the necessary write speed.
Put the card in your computer and format it with the exFAT filesystem instead of FAT32. Yep, that’s it. The default filesystem is the major difference between SDHC and SDXC cards and formatting the SDHC as exFAT is enough to fool the Sony camera. I think the exFAT requirement is actually present because exFAT supports files larger than 4GB in size while FAT32 does not; XAVC-S can result in some really large files compared to other modes.
The camera and apps will complain and beep about the card “not being compatible” but it’ll record XAVC-S at the full 50Mbps 60p rate to your card despite the annoying protests.