According to Wikipedia, "The number of root directory entries available is determined when the volume is formatted", so perhaps the manufacturer formatted the card with only 256 entries.
If this is the case, it's not a bug in Ubuntu. If reformatting doesn't help, then please re-open this bug.
According to Wikipedia, "The number of root directory entries available is determined when the volume is formatted", so perhaps the manufacturer formatted the card with only 256 entries.
If this is the case, it's not a bug in Ubuntu. If reformatting doesn't help, then please re-open this bug.