Never used before these black plastic cable carriers but now I got them and they are 1.5" wide by 1/2" high. They are installed on the A axis (40" Long) and X axis (32" Long) and doing a good job but when I move the A axis I hear an occasional noise like krack-krack which I can't pin point but I'm sure its coming from the cable carrier. I have no problem with the X axis carrier but it has less cables inside.

Do you normally apply any lubricant on the joints of these carriers and if yes what kind?

I do have a silicone based spray lubricant but would it affect the cables inside the carrier?

Even so-called self-lubricating materials benefit from initial lubrication. Silicone spay is an excellent choice for this and it won't hurt the cables.