Incorrect cyclic guesses error

[baggepinnen]

The furuta pendulum simplifies to the correct 4 variables

julia> ssys
Model model:
Equations (4):
  4 standard: see equations(model)
Unknowns (4): see unknowns(model)
  elbow_joint₊phi(t): Relative rotation angle from frame_a to frame_b
  shoulder_joint₊phi(t): Relative rotation angle from frame_a to frame_b
  shoulder_joint₊w(t): angular velocity (rad/s)
  elbow_joint₊w(t): angular velocity (rad/s)

but ODEProblem fails with

ERROR: Cyclic guesses detected in the system. Symbolic values were found for the following variables/parameters in the map: 
(lower_arm₊body₊a_0(t))[1]  => (lower_arm₊body₊a_0(t))[1]
In order to resolve this, please provide additional numeric guesses so that the chain can be resolved to assign numeric values to each variable.           

despite initial condition being provided for the 4 state variables

https://github.com/JuliaComputing/Multibody.jl/blob/linear_scc_branch/test/test_orientation_getters.jl#L43