Just bought a second hand pair of Nexus 6 stands as I thought they might be significantly better than my old single pillar jobs. However they still wobble slightly when the speakers are mounted on them! They wobble on the pillars as opposed to the whole stand so I don't think it's to do with the floor. I have filled all 3 columns with sand so they are heavy as **** and all the bolts are done up tight. At the moment they are spiked and stood on a laminate floor if that makes any difference?