I am having similar issues and i am NOT using TweakScale. Most of it for me seems to revolve around the Mk1-2 command capsule, as the only vessels that this issue has occured on used that particular part. Mods: KSP Interstellar 0.90 update 0136 Station Science 1.4 Kerbal Attachment System 0.4.10 Crowd Sourced Science 1.4.0