When you design a noise file you have to ensure that the sample rate is 1/2 the clk rate. For example if you have a noise profile that is up to a 30 Mhz sample then you need a CLK statement in the header set to $CLK 100 Mhz.. If you do not use the CLK in the header then the noise generator will pick the last Sample rate that was used by the previous generated noise profile. So if the previous file calculated used a CLK of 12.5 Mhz then the next time you tried to run a noise profile that needed a 100 Mhz CLK you would get an Error. The error displayed would indicate that the sample rate of the profile is less than 1/2 of the clk rate.
DLS 5500 and DLS 5800 have three valid CLk values 12.5 Mhz, 32 Mhz or 100 Mhz..