Wow did you figure this out all on you're own? If so very impressive. This is the way forward and you're doing all the right things. Repeating is better than blocking. It sounds like you're stopping your repetitions by postponing (pausing) before the feared sound. If you keep on this path is avoiding avoidance, eventually you will go right to the feared sound and let yourself stutter on it instead of postponing, so great work. One thing I will add is you don't need to work on this all day every day to make change. Trying to work on it all day is very exhausting and you can make real change resisting avoidance 2-5 times per day and that is sufficient for change. Change also likely won't be linear so don't worry if you backslide at times, those gains you've made are not gone!