As for the male Guinea, unfortunately this is where it gets confusing. The male also makes a one syllable call and it also sounds like "chi, chi, chi". This is their standard call, the one they use all the time although they can do the trill too. You'll hardly ever notice the trill, but you'll know when the "chi, chi, chi" machine goes off! You might want to invest in some earplugs. *sigh*
Ok, so to recap....the female can make the female call and the male call but the male can only make the male call....got that? It goes like this:
Female: 'buck-wheat, buck wheat' & 'chi, chi, chi'
Male: 'chi, chi, chi'
It confused me at first too, so I've prepared a few video clips for you.
This second clip here is one I posted a few years back when someone emailed me asking how to tell the males from the females. It's only after I happened to look at how many times it's been viewed that I decided it might be time to post about this and make a new clip. I hope this helps you when sexing your Guineas.
There are several common 'farm wives tales' about sexing guineas, none of which are 100% accurate. I discussed this awhile back in this post: The Guinea Wattle Myth. The only proven sexing method is by their call and unlike most chicken chicks, guineas cannot be sexed at hatch.