We numerically analyse the effect of coupling strength random fluctuations on both dynamic and static soliton switching in symmetric nonlinear couplers. As in the cw case, the effect is generally found to be strong only near the switching regions. In the dynamical switching regime, the effect appears to increase with the length of the coupler at a rate twice as large for odd multiples of the linear coupling length, π/2, than for even ones. In the static case, the region of bistability shows the greatest change in the effect of random fluctuations, with a maximum at exactly the first bifurcation point. The solitons also appear to be quite stable against the random fluctuations in the sense that no pulse distortion or emission of dispersive radiation was detected.