Running backblocks -n will often fix them (non-destructive read/write - it causes a rewrite of every block on the device). Don't do it often or you'll cause ex

Running backblocks -n will often fix them (non-destructive read/write - it causes a rewrite of every block on the device). Don't do it often or you'll cause extra wear, but if you find yourself getting random errors from the SD card, give it a try.