2 Tone VerilogA signal source does not work in Harmonic balance

Hi all,

I have a problem to get a Verilog-A signal source with two output tones to work in harmonic balance. So far my code looks more or less like this (deleted some calculations):

// VerilogA for 

`include "constants.vams"
`include "disciplines.vams"

module emulator(out,gnd);

output out;
input gnd;

electrical out,gnd,internal1,internal2;

real freq1,freq2,amp1,amp2;

parameter real  centerFreq = 70G;
parameter string fundname1 = "rf1";
parameter string fundname2 = "rf2";

analog begin

freq1 = 10M;

freq2 = 100M;

amp1=1;

amp2=1;

$cds_set_rf_source_info ( fundname1, centerFreq + freq1);
V(out,internal1) <+ (amp1)*sin(2*`M_PI*(centerFreq+freq1)*$abstime));
if (twoTargets>0)
begin
$cds_set_rf_source_info ( fundname2, centerFreq + freq2);
V(internal1,internal2) <+ (amp2)*sin(2*`M_PI*(centerFreq+freq2)*$abstime);
end
else
V(internal1,internal2) <+ 0;
V(internal2,gnd) <+ 50*I(internal2,gnd);

$bound_step(0.01/(centerFreq+freq1));
end
endmodule

With the help of a blog post I am able to make a signle source run in transient and Harmonic Balance. However when I try to use 2 sources harmonic balance will not calculate the correct results!

What am I doning wrong here? How to use $cds_set_rf_spurce_info() correct in my case?

Thanks in advance!