I updated the EXE to try and clean up the sound when using the heaphone option.
It did not seem to help, however, I did make the audio a little more efficient.
The HDMI sounds great so it may be down to a buggy driver. I noticed the same issue with other programs. I could try different sample rates to see if it makes a difference but if i go too high the EXE won't fit on the forum.
Actually, this is like my "Hello World" type program on the PI, so I will probably just move on to something more interesting