We investigate the conductance of a Normal-Normal-Superconductor (NNS) junction, in which current injection destroys superconductivity in a small region N of the superconductor, with a size varying with the applied voltage V. Voltage-dependent de Gennes-Saint James (dGSJ) bound states appearing in the N slab lead to two distinct sets of conductance oscillations. We show that this effect significantly alters the conductance of systems for which $kappa^2v_F sim 10^9$ m/s such as pnictides ($kappa$ and $v_F$ being the Ginzburg number and the Fermi velocity, respectively), and we discuss their consequences on the identification of the bosonic modes of strongly coupled superconductors.
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