The SD Card requirements are a little bit confusing.
SD Requirements to Update the pedal firmware you need:
1 - SD Card has to be SDHC type (the HC stands for high capacity, and almost every SD card made in the last 10 years is the HC type).
2 - The SD Card has to be formatted to FAT32. (With some newer SD Cards that are higher capacity (usually 64GB or bigger) windows wants to format them FATex which is sort of a pain, but there's utilities you can use to format them to FAT32).
If the conditions of above aren't met, you'll see the mode leds flash red when the pedal starts up. If you're not trying to update the pedal, but are using the looper that's ok.
- For firmware updates we don't care about the V30 (V30 means it's video speed class and means that it can maintain certain data throughput rates without pauses).
- Doing the firmware update shouldn't corrupt other data on the card ( but we always recommend backing up anything else on there anyways).
SD Requirements to use the looper:
- SD Card has to be HC (like above), and has to be V30. ( The V30 is important because we have to maintain some higher data throughput of audio without dropping out. When we didn't enforce this people were experiencing dropouts because some cards couldn't keep up).
If the V30 requirement is not met, you'll see the preset leds flash red when you're holding down the middle and right stomps trying to enter the looper mode.
- The formatting (FAT32, FATex ) is un-important for running the looper. The looper writes the audio to the card as raw data, so in many cases it will corrupt the filesystem (and files) on the card.