Recently, while watching Walking Dead, I heard "sufficient" pronounced differently from what I have learned twice. I learned it with a "sh" but they pronounced it like the original "suffice". Checking multiple online dictionaries indicate the way I've learned it is correct. Where does the different pronunciation come from? Is it a dialect?
After trying to find the part again I can't say for sure anymore that it was Walking Dead (see comments). But I definitely heard it twice in something I watched recently and as far as I remember I only watched US productions.