Is there any special way to start a clock - SystemC 2.3, 2.2?

Could some SystemC guru please help ?
I have in the test harness for a simple master slave
JK flip-flop the following clock:
sc_core::sc_clock clk("clk", 2.0, sc_core::SC_PS, 0.5);
.........
sc_core::sc_start(10.0, sc_core::SC_PS);
sc_core::sc_stop();
return 0;
}

However, the output always looks like:
0 jkmsff_0.inv_0 1 0
0 jkmsff_0.nnd3_0 0 1 0
0 jkmsff_0.nnd3_1 0 1 0
0 jkmsff_0.nnd3_1 1 1 0
0 jkmsff_0.nnd2_o2_0 1 0
0 jkmsff_0.nnd2_o2_1 1 0
0 jkmsff_0.nnd2_0 1 0
......
.....
Where the first 0 is supposed to be a time stamp
extracted as in an inverter

SC_MODULE(inv)
{
sc_core::sc_in<bool> din;
sc_core::sc_out<bool> dout;
bool b0;

void inv_proc0()
{
while(1)
{
wait();
b0 = din.read();
dout.write(!b0);
std::cout<<sc_core::sc_time_stamp().to_seconds()<<" "<<name()<<" "<<b0<<" "<<!b0<<std::endl;
}
}

SC_CTOR(inv):b0(false)
{
SC_THREAD(inv_proc0);
sensitive << din;
}

~inv(){}
};

The results are identical as SystemC 2.3.0, 2.2.0

Is there any glaring error ? I have used similar clocks
over and over in other modules, and they work just fine.
Any hints, suggestions would be of immense help.