What are these note heads like diamonds in this cajon notation? Video

hollywoodrox

Hi, so I’ve figured out  which line is the bass & which is the higher note 
  I can’t see the difference between the X notehead (which I assume is a snare slap ) and the little black diamond notehead . In the video they look and sound the same as each other 


  https://youtu.be/VLVdK6jpt2g?si=B4YwQ63UVPTpYg7W

hollywoodrox

And in this one too . I know you’re dead clever on here 
https://youtube.com/shorts/h4o3Qtvn1ZQ?si=DcGcFAlMaLFOLi8h

hollywoodrox

Well that’s rather odd in another video he explains that the note under the X is a ghost note 
  Yet he’s not playing it ghostly here at all it seems to have the same force as the others on the snare bit