The stability of soliton propagation in a system with spectral filtering and linear and nonlinear gain is investigated numerically, assuming various input waveforms. Our results show that merely giving a linear frequency chirp to the initial pulse is not effective in suppressing the background instability in bandwidth-limited soliton transmission. However, it should be possible to achieve relatively stable pulse propagation over long distances by the use of a suitable combination of linear and nonlinear gains. Truly stable propagation of arbitrary-amplitude solitons can be achieved only in a system with purely nonlinear gain. A new soliton compression effect is demonstrated both for fixed-amplitude and for arbitrary-amplitude solitons. For fixed-amplitude solitons there is an optimum propagation distance for maximum pulse compression, whereas for arbitrary-amplitude solitons the pulse width remains practically constant after some oscillations in the initial compression stage.