you mean with both kernels? strange!!!
video recording and playback is way laggy for me!! It's stock ROM with Stock 562 based rootable kernel!!
but i have to say i test it both kernel the stock and the xray{4.0.1} and they all have the same results but i feel xray{4.0.1} is less lag than the stock
anyway try to reflash the rom and if its is the same results try to reflash kernel and the rom
hope u luck dude