All of the above…add mass to your stands or upgrade to a more structurally inert stand. Mate the speaker to the stand with sorbothane sheeting (AudioQuest sells a sheet that can be cut to treat a pair of speakers) and if budget allows, invest in Gaia feet. If on a carpet, IsoAcoustics has carpet piercing spikes that go under the Gaias.
The cheap version is Monoprice Monolith stands, play sand filled baggies, and Blu Tack mounting putty.

