Many words are pronounced in a skewed way in non-native english speaking demographics. I've heard almost everyone I meet saying Software-'Soot' instead of 'sweet', 'Adobee' as 'Adob', 'Orcut' as 'Orcoot', and 'alarm' as 'alaram'. When I asked them if it does not come out the way it is supposed to be when they are reading it, it actually 'didn't sounded like that in our head.'

I'm from India. I went to a school (started by a British-Indian family) where the students speaks so many dialects, that English was the only common denominator and I remember a lot of emphasis was given on pronunciation and the like. Getting the right lyrics of English western songs was one of the common pastime.

block soot possibly?

(Not a native speaker.)

I think I'm a fairly proficient English speaker. I know it should be pronounced sweet but I instinctively default to suit.

Yes, this is exactly the reason why.