When I was at school, we were taught that unstressed syllables were almost always pronounced the same, like the second n in Londn (= London).
I have ties with a town which was as often misspelt as mispronounced: Folkestone.
Correct: foe-kstn.
Correct: Folkestone. Wrong: Folkstone, Folkeston, Folkestown, Dover.
Of course, there are those who think Eurotunnel starts (or finishes) at Dover They are wrong

.