I have a friend that has a 2004 crossfire. the six speed tranny right after she lets the clutch out in first It pops out into neutral with a bang and it some times does it in third as well. what is this?

 

How long has she had it?
Miles?
Most likely she is not getting all the way into gear.
I have noticed in my 6 speed when I am at a stop putting it in first, I have noticed 2 clicks as pushing all the way into first.
Put 20k - 25k Miles on car since I noticed.
Has the oil been changed in transmission?
If not you can do it yourself easy so when you pull the drain plug out look at the magnet on the plug for shavings, and you can inspect oil for shimmer.
Some shavings are fine but if a excessive she might have rounded the gears.
Which she can still drive it but just needs to be more careful shifting

 

She has had it for four years, the car has something in the 40,000 mile range. She says she has it all the way in gear but it has not had the tranny oil changed sense she's had the car. I will look into the oil situation and see. Now I have a place to start.

 

I have had mine pop out a couple times and it was due to it just not being completely in gear, when I thought it was.
Checking the oil is a good determination on how she shifts

 

Worst case scenario, it's the syncros.
Was her car built before Dec. 2004? From what I've read in the past, I think there may have been a factory service bullitin on the problem.