Heavy Meson Hyperfine Splittings: A Puzzle for Heavy Quark Chiral Perturbation Theory

We show that there is a large discrepancy between the expected light flavor dependence of the heavy pseudoscalar--vector mass splittings and the measured values. We demonstrate that the one--loop calculation is unreliable. Moreover, agreement with experiment requires the leading dependence on SU(3) symmetry breaking to be nearly cancelled, so that the heavy quark mass dependence is unknown and the expected dependence on the light quark mass is not realized.