Two-dimensional Riemann problem for rigid representations on an elliptic curve

We consider a generalization of Riemann-Hilbert problem on elliptic curves. For a given elliptic curve and irreducible representation of free group with two generators we construct explicitly a semistable vector bundle of degree zero obeying a logarithmic connection such that its monodromy over fundamental parallelogram is equivalent to given free group representation, monodromy along a-cycle is trivial and monodromy along b-cycle belong to certain orbit.