It may be possible that it is not the ESC that is making the cogging sound. It may be one of your differentials, look at you manual and you will see the CV shaft and a pin that the gear leys over. That pin can slippe behind that gear if there is no steel shim between the diff cup and the pin.
To check this you may need to remove the drive shafts and check the amount of play. Grip the CV cup and pull and push tours the diff cup note the amount of play. There needs to be no play there (in and out movement) but the shaft needs two spin freely. You can see where the pin is slips (rubbing marks) on the back of the gear. When you are shimming the CV shaft end play you will want to check the planetary gears you may need to shim them closer this will not tighten the clearance it is just to get more of the gears to meshes (more tooth to tooth). Remember the nitro engine does not have the torque out put brushless has, and the diff tolerance was not engineered for BL. So we will need to tighten up the tolerances. Granger CO. has a large selection of shims. OFNA hyper 8 is my buggy and I ordered Shims 24@ 4mm x 6mm x.26mm and 12@ 6mm x12 mm x.26mm