Khaki Campbell hen or drake? *picture

[Cuckoo4Cochins]

I've had my duck Ivy for about 10 weeks now. I have always assumed she was a male because her mates beak turned a yellow/green color and hers remained a slate color with a black bean. I've heard you can determine gender from the beak color. Here's a picture (sorry for the low quality)

 

[Amiga]

Quacking or quieter, whispery voice?

 

[Cuckoo4Cochins]

I can't really tell with her. The other KC is for sure a male but makes very loud noises like a female. They both sound the same.