I'm an ASIC agent, your delay may be due to how long it takes for the issuing body to put it into the system, print the card, let you know it is ready etc, add more delays if there are third parties involved such as Australia Post. There is no point in contacting Auscheck as all they do is the actual background check part. Not a great idea to contact them and have a go at them.
We are turning them around in about a week with a very few exceptions, that's from initial in person document check to handing over the card, because apart from Auscheck we do everything in-house.
So if you are not happy, go to another issuing body but make the most of it because when the Govt abolish the independant issuing bodies and start doing it all themselves as a Single Issuing Body, then you will encounter a whole new level of "delay" and "incompetent public servant"
Aviation Security Identification Card (ASIC) Issuing Bodies (auscheck.gov.au)