I decided to try to reproduce this issue with a new program that does little more than Wait() on Ctrl C & D but the new program only receives single keypress events - as it should. So I modified it to be a little more like the initial program that has the issue by creating an additional message port and adding its signal bit to those being Wait()ed for - still, only single keypress events are coming in.

The other major difference between this program and the initial one is that the latter creates a child process. I'm not sure if I'll pursue this any further though...

[ Edited by ausPPC 23.01.2017 - 05:50 ]