occasional core crash when welding (?)

[InvalidArgument3]

20:38:29.3624 [INFO] Keen: SpecCores:Checker: Step=3 System.IndexOutOfRangeException: Index was outside the bounds of the array.
at System.Array.Clear(Array array, Int32 index, Int32 length)
at System.Collections.Generic.List1.Clear() at MIG.SpecCores.Sugar2.GetConnectedGrids(IMyCubeGrid grid, GridConnectionType with, List1 list, Boolean clear)
at MIG.SpecCores.ISpecBlock.GetIsStatic(Boolean oldValue)
at MIG.SpecCores.Lazy1.get_Value() at MIG.SpecCores.ISpecBlock.GetLimits(Boolean hooks) at MIG.SpecCores.SpecBlock.CanBeApplied(List1 grids, GridGroupInfo info)
at MIG.SpecCores.LimitsChecker.Phase_1_CollectInfo(List`1 grids)
at MIG.SpecCores.LimitsChecker.CheckLimitsInGrid(IMyCubeGrid grid)