I get this on mine and am a slightly heavier rider. Run them at about 115psi. Mine are the uturn versions and often often find after big hits they wind themselves down which is really annoying.
Did an uplift day at Cwm Carn a few few weeks ago and by time I reach the bottom of a run i found they had wound themselves right down to minimum travel which was annoying and made the bottom section very sketchy!
I reset the pressures every month or so and never really find they have lost most pressure. When I called TF Tuned a couple of weeks back they suggested the helix might be damaged in the left leg but this would be about £200 to fix and as my LBS replaced all the seals are serviced them two months ago I am reluctant to do this.