Jagdave

Has anybody out there experienced a loud backfire in the intake when switching on the ignition?
Here's what happens - every time I park the Z and leave it for a couple of hours, when I come to start the car but before cranking the engine there is a LOUD explosion in the intake manifold. After a lot of head scratching and theorising we discovered that there is a spark generated at all six ignition coils when the key is moved to position 2. This is igniting the unburnt fuel vapours in the intake manifold and so causing the backfire. We have checked an unmodified car and this spark is not present so we have concluded that it is being generated by the Emanage unit.
The car has a ProCharger, big injectors with a return system and the Emanage is fitted with the optional injector and ignition harnesses, the latter has the diodes fitted and they are okay.
If anyone has had this problem with the GReddy unit and has fixed it please let me know what you did - these explosions are loud enough to bring the neighbours out and I'm worried somethings going to give!
Thanks,
Dave