I haven't heard of any problems between the Avenger PTT and a repro. But I guess it's fairly rare to dish out for a PTT and not a headset.
Perhaps you could post in this thread:
http://www.airsoftcanada.com/showthread.php?t=163816
Secondly, I would send an email to SRS Tactical. They're super friendly, and helpful. They'll probably be able to tell you whether or not the PTT differs from a knockoff Z-tac PTT. If not, they'll likely tell you to send it back, so they can test it themselves.