Sometimes the projector hangs unevenly even if all screws are tightened according to the manual. The reason is that some models (for example, LG Cinebeam HU710PW) have mounting points shifted toward the front, so the center of gravity does not align with the suspension axis. In this case, make sure the spider mount is properly adjusted and centered. Try repositioning the spider arms so that the weight is evenly distributed. In most cases, this solves the balance issue.