tried multiple sd chips, all under 32GB, formatted with SD formatting tool, sd not detected with either sd library or sd_mmc library, and does not detect pin presence either. the rest of the board is fine.
It might be worth taking a look at the SD card slot pin area and see if there happens to be a solder blob/short between 2…if you find one and are comfortable soldering you can try to remove it and we’ll honor your warranty
If you don’t find much it is likely a defective unit - Was it purchased from us? If so head over to Returns - SparkFun Electronics (contact vendor if purchased elsewhere) and we’ll get ya squared away