If you are seeing engine data periodically drop to zero or only update sporadically, it could be an intermittent connection issue. Double check connections to make sure they are tight and that the wires are not slipping out of their crimps. If you own a JS501 JIB there are more specific instructions here: Data intermittent or drops out JS501. Not sure which JIB model you have? Check here: Which JIB model do I have?