  In this paper we discuss the problem of small frequency approximation of the
causal dissipative pressure wave model proposed in \cite{KoScBo:11}. We show
that for appropriate situations the Green function $G^c$ of the causal wave
model can be approximated by a noncausal Green function $G_M^{pl}$ that has
frequencies only in the small frequency range $[-M,M]$ ($M\leq 1/\tau_0$,
$\tau_0$ relaxation time) and obeys a power law. For such cases, the noncausal
wave $G^{pl}_M$ contains partial waves propagating arbitrarily fast but the sum
of the noncausal waves is small in the $L^2-$sense.
