Anyone have issues with the upthrust device on the Velino units? We have several units at a large mall that continually get upthrust faults - sometimes multiple ones in a day. They have all been set and tested to 5 mm per code. We even went so far as to steam clean all the steps and apply a silicone spray on the risers to make sure the steps weren't binding up. None of our other service mechanics in other markets have heard of the issue, so we have to be missing something. Any help would be greatly appreciated.