yup my tsunami did that especially on the back one. the local hobbytown usa had a bunch of hpi stuff in 30% off sale bins so i went scrounging. i found my worst problem was the cup that the brake disc runs on. i found hpi ones part number 72107 is the same part but much heavier duty looking. I also bought hpi part number 72083 which is the rear drive shaft with a universal mounted on the differential end instead of a cup. this has gotten me a rear driveshaft setup that has NO play in it at all so it shouldnt wear groves in it and bind the axle.

does your snap the very tip off of the front by the brake disk? you can add an extra o ring (make one out of the fuel line) inside the front cup and that will space the driveshaft back enough to keep it from hainging in the grooves. I have found the driveshafts fit very loose, and since the back one is soo short it has no flex to it and just snaps. ive broken like 3 rears in my car HPI part number A553 is the exact same shaft as the stock one.

hope this helps