Cloning Issues

So here is my issue.

I am fairly new to cloning and in my previous experience with cloning some random bag seed I had a near perfect survival rate. Roots within 2 weeks, ready to transplant from 16 oz. cups in 3-4 weeks. No problems what so ever.

I recently acquired a new strain, not sure what it is, if anyone has read my last few threads there are pics of them bomb-diggity bitches in them.

Well, all attempts to clone this strain have failed. I followed the same procedure. I get some fresh water, I use a powder rooting hormone, clean razor and scissors. Here is what I do. Cut a lower branch, strip off bottom 2 fan leaves, place in water. I let them soak for a 2-3 minutes then take them out and cut a clean 45 degree angle, I also shave a thin layer off the stalk, about a inch up to expose more of the stalk. Then I place them into the powder and coat well. Place into soil and that's it.

Keep in mind with the before mentioned strain, I had a nearly perfect survival rate (lost 1 I believe). With this new strain, no luck out of 12 I think, all 12 have deceased.

Could this strain just be super hard to clone? Is my technique flawed? It worked perfectly fine before with over 20 clones. As of now I plan to re-veg two of these ladies and try again. I also have 4 seeds of the same kind that just popped today.

Any suggestion, help would be lovely. Peace.

No difference in lighting, soil, (or other medium) water ph, heat...?

Do you dip the cutting into the powder, or sprinkle it on?
If you dip the cutting into the rooting powder, do you tap-off the excess powder? A big glop of hormone powder isn't necessary, and is likely problematic. (it's not a band-aid for the cutting...the idea is to have the hormone absorb into the plant tissue, and promote rooting) Also, if you do dip the cutting directly in the jar, are you contaminating the powder?

I use the same technique to clone, but before I dip-n-tap, I make another clean cut under water, about a half inch from original cut. This prevents the plants natural suction from sucking-up an air bubble, which is fatal.
-or-
you need to start thinking seeds, lol. (kidding)