I had some problem with the center one-way on the 414M2. Because the layshaft have flat spots for setscrew (for when you're using 4WD pulleys) the edges of the flat spots tend to catch the pins inside the one-way bearing. Check if the pins inside the one-way are worn down and out of alignment inside. When it is out of alignment, the one-way will be there sometimes and sometimes it will lock like a 4WD pulley, making the car feel like it is glitching. There is really no fix that I know of for this, but an option you have would be to replace the center layshaft with a silver one from the 414x (call Tamiya on this) and it is of a harder material and it is less likely to have the edges on the flat spot deform and catching the one-way pins (I'm using the 414x shaft on my car at the moment)
If you're referring to the front one-way, then I'm not sure what can be causing it.