Comment on "Dynamics of Charge-Density Waves Pinned by Impurities"

In a recent Letter Klemm and Schrieffer(1) (KS) have attempted to calculate the dynamics of a single domain of a charge-density wave (CDW) pinned to impurities.(2) They give results for the dc current voltage characteristic, and also suggest that the impurity averaged current-current correlation function shows coherent oscillations. Their paper contains several serious errors which invalidate the results even for the very limited case considered of independent domains.