  We study {\em dynamic} melting of confined vortex matter moving in
disordered, mesoscopic channels by mode-locking experiments. The dynamic
melting transition, characterized by a collapse of the mode-locking effect,
strongly depends on the frequency, i.e. on the average velocity of the
vortices. The associated dynamic ordering velocity diverges upon approaching
the equilibrium melting line $T_{m,e}(B)$ as $v_c \sim (T_{m,e}-T)^{-1}$. The
data provide the first direct evidence for velocity dependent melting and show
that the phenomenon also takes place in a system under disordered confinement.
\pacs{74.25.Qt,83.50.Ha,64.70.Dv,64.60.Ht}
