We present the measurements of broadband voltage noise generated by the driven vortices near the peak-effect regime of a thick amorphous Mo$_{x}$Ge$_{1-x}$ film. We focus on a change in voltage noise as the vortex system undergoes mode locking (ML), which is a dynamic resonance between the ac drive superimposed on the dc drive and lattice-oscillation modes excited collectively. By sweeping the dc current $I$ at fixed ac drive, we find the step-like structure in the current-voltage ($I-V$) characteristics indicative of ML. At high frequencies $f$ (but well below the ac-drive frequency) the noise spectrum is $f$-independent. We find a trend for the amplitude of noise (at high $f$) to decrease in the ML step.
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