Ahhh, the joys of paying too much attention!
I too cannot deal with people who have poor pronunciation and even poor Enunciation!
I used to get into trouble for it all the time.
I was told it was rude to correct people (especially folks older than I am) but I could not stop!
(Oh, and yes, it IS rude...sometimes we just do not care though, eh!?)
Then one day, someone from a different country, and a different pronunciation guide, corrected me! WHAT?!
So, I learned that I did NOT know everything, and now I am a lot more careful about it. I also have found that there are a large number of words that are rarely spoken correctly. Looking in a good dictionary will provide you with the "standard" pronunciation for words, you have to practice a bit to read the little wierd letters and how they are supposed to sound. The root word or where it comes from language wise will also make a difference, another good thing about the dictionary, it will tell you a word is from the fr-French, or lat-Latin.
The word Aluminium- like aluminum foin. in the US we tend to say Al-um-in-um in other parts of the world it is Al-uu-min-i-um. who is right or wrong?
We leave out a lot of letter sounds in teh US, and also in some regions, we add them in where they are not , like the word Wash, some people say Warsh. I always found that disturbing. Or the word ASK, as in "I want to ask a question." many people sasy AXE- in stead- ARGGG! I say, but what are you going to ? Language evolves through use and regionality. That is how accents and dialects get developed.
Consonant sounds blend and change. Vowels are different from region to region, why do you think the Y and W are sometimes considered a vowel? There are a number of words that do not have any other vowels than those. They are common letters/sounds in other languages.
As English is a polyglot language, we have to learn to adjust just a little and be forgiving of all unusual pronounciations.