  For metallic point contacts with Be and Al the magnetoquantum oscillations in
the contact resistance have been investigated as a function of the applied
voltage over the contact. For one set of point contacts the oscillation
amplitude is found to vary nonmonotonously with the applied voltage with
similarities to the point-contact spectrum of the electron-phonon interaction.
The other part of the investigated point contacts shows a decrease of the
oscillation amplitude with increasing bias voltage. For the understanding of
the voltage dependence of the amplitude of the point-contact magnetoresistance
oscillations the influence of nonequilibrium phonons generated by the
ballistically injected electrons will be discussed.
