Try to track down the source of the problem. Make a copy of your form, and then working with the copy, remove items one-by-one until the flickering stops.
Then, starting with another fresh copy of your form, try removing just the offending items. If the flickering stops again, then you need to figure out why those items are causing the problem. If not, then you need to continue to try to locate what combination of things could be causing the flickering.
Also, for a sanity check, make sure that not all other forms with repeating tables flicker. If they all do, check your video drivers.
Also -- one other thing, if you have a background graphic, try removing that.