"ou ka nan enka, ou ka nan deka, apre sa res la se pwoblem" Should I say though i understand what is said, i don't get it :)

That's a pun.
I don't think it can be translated in English.
I'm not sure how well i can explain this either :)

It feeds on the fact that "KA (fourth)" the denominator in ¼ (enka), 2/4 (deka), 3/4 (twaka) is read as "KA" as in "trouble, tèt chaje, etc..."  and guess what would 4/4 be?  If you guessed "kaka", you're right:

Mezanmi nou nan ka!
Nou ka nan 1/4
Nou ka nan 2/4
Nou ka menm nan 3/4
men si nou nan 4/4, nou chire!

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