Terminal "n" in South Vietnamese Accents

All the resources I have for learning Vietnamese pronounciation are Northern accent. I'm familiar with the differences in R etc but I noticed something recently during a trip to Vung Tau/Ba Ria: the locals out in the countryside don't pronounce words like bốn with an "n"...they seem to be using an "nh", so a word like bốn sounds like bốnh. I haven't come across this on any discussions on the difference between Northern and Southern accents, thought I'd share and get some opinions on it.

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u/noellarkin — 11 days ago