Under many conditions the G2 creates an extreme overload of sound and backs off till another jolt of sound arrives. It happened at a rural wedding with the groom wearing the transmitter and at a dance recital hooked to a phantom converter at the stage. To complicate things the overload is not consistently bad. Whenever I hook the G2 up at home and move around the sound is perfect. Any ideas I can try?
I have a G3 system that works great under the same conditions.

That sounds like RF problems with another TX in the area on an adjacent (or very close frequency) could be another radio mic, TV transmitter etc.
This sort of thing is going to occur more often as radio mic bands get shifted and condensed.
Good RF practices are becoming needed these days.

I agree, interference.
I'll assume you have done your due-diligence prior to shooting, checking for open channels in your area and scanning or a manual search. Sometimes that's not enough, cell phones and other wireless devices in the immediate area. Proper trans/receiver and antenna placement play into the game as well.
It's not a set-it and forget-it thing like a $20 cable.
A more expensive ($3k) system will reject 'outside' signals 'a little' better if everything else has been set-up optimally.

Thank you for your suggestions gentleman. RF interference sounds like an answer. The problem is if I check the wireless before the event it is usually good. After this ad audience with cell and other devices and sound tech's coming in at the last minute firing up their equipment. I do appreciate your ideas but I'm not optimistic I can solve an RF problem once the event starts and I'm stuck behind the camera.

Yes, that is always the risk of using wireless. Even the best, most expensive, most sophisticated wireless gear is never completely immune from interference and RF noise. And, as you say, covering one-time, live events (like weddings, etc.) and especially with a minimal crew just makes it harder to deal with situations.

No preventive measures before hand can completely immunize you from interference from an audience full of little transmitting devices. I have gone back to wired mics in many places where wireless was once ideal.