I have a final answer to this issue. This for the Turtle Beach PX-22 Headset with a broken plug. The plug is inserted into the Amplifier which in turn plugs into a PC via a USB connector. The plug needs to be low profile or narrow as it wont fit into the amplifier otherwise.
The following cable wire colour to 4 pole plug as follows:
Green - tip;
Red - ring 1;
White - ring 2;
Blue and copper twisted and soldered to - sleeve/ring 3.
I am pleased to say this works perfectly. Additionally, I bought a new cable - 4 pole plug to 4 pole plug. Cut it in half and connected the wires based on 'buzzing through' to the plug with my multi-meter as the internal wire colours in the replacement cable were different colours to the turtle beach internal wires. It was much less bother than using a brand new 'blank' narrow profile 4 pole plug (too much of a challenge to my soldering skills and eyesight!).
I hope this helps for anyone with the same or similar issues.