Sometimes the cursor, as it's moving along the timeline, will kinda hang up inbetween tracks and ping pong back and forth for a while... anyone know what causes that? Thanks.
Have you got plugin effects running ? This may be causing your cpu to run out of steam for real-time preview.
Unfortunately (CDA5.3 anybody ?) any plugins on each individual event *ALL* effectively run concurrently, along with master-bus FX. This is a CPU hog behaviour.