  We present a theoretical description of the differential conductance of point
contacts between a normal metal and a multi-band superconductor with extended
s\pm pairing symmetry. We demonstrate that the interband impurity scattering
broadens the coherent peak near the superconducting gap and significantly
reduces its height even at relatively low scattering rates. This broadening is
consistent with a number of recent experiments performed for both tunnel
junctions and larger diffusive contacts. Our theory helps to better evaluate
the energy gap of iron-based superconductors from point contact Andreev
spectroscopy measurements.
