3Delight for Maya can change the current time while rendering in two cases: when rendering a frame sequence and when motion blur is enabled. If motion blur is requested, the blurred objects need to be sampled a number of times during the frame’s interval in order to detect the extent of their movement. This means that the current time will move a number times to sample the movement, and then jump back to the current frame once the rendering is done.
Since dynamics are computed incrementally the time jumps introduced by 3Delight for Maya may yield consistent results. To avoid this problem, the dynamics computations need to be exactly the same for a given frame, regardless of what was the previously played frame. One way to achieve this is to cache the dynamics results. It is highly recommended to use Maya disk caching system when working with a scene that contains dynamics. Refer to the Maya documentation for more details about this; look into the Solvers and caching book in the "Dynamics -> Dynamic and Effects" section.