Troubleshooting stretching/twitching SMP nodes

[Frosferes]

I have a bug with some SMP constraints on a body I've been working on. Constraints that are meant to be used for opening of the anus/vagina are stretching and twitching even when nothing is intersecting with the associated collision mesh.

 

 

Here the collision meshes have been made visible for debugging and have been commented out of the config file so the issue is with the bones/constraints and not the collision meshes.

 

The amount of stretching is inconsistent. Sometimes it's minor and other times it's extreme, but the twitchiness is usually there. Using the 'smp reset' command restores how the mesh is supposed to look but as soon as the character moves it stretches out again.

 

Is anyone aware of common causes for this kind of behaviour or how to troubleshoot it?