Ah, lack of awareness :)

Unfortunately, changing to "param1(\"%f\")" results in param1("0.000000")

The only other calls I am making before this are:

csound = new Csound();
csound->CompileCsd(csdFilePtr);
csound->Start();

Should I be declaring the channels somewhere prior?

I also noticed the Software Bus and chnexport, which might be an alternative for me to look at ?

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