A friend of mine who is a long time Thailand resident and former university instructor tells me that there is a version of Thai spoken in Korat called Tai Deung.
Can anyone enlighten me? Perhaps those of you with Thai partners could ask them about it?
Yes, I have solid confirmation.
Thai Deung (with a falling tone) is the name of a variant of Phasaa Korat that is found around Amphoe Phathai. Yes, it is based more on Central Thai than on any of the Lao-derived languages of Isaan, and is described as a type of Phasaa Korat. In fact, the way I heard it, it seems more like a peculiar pronunciation of Korat than a separate dialect.
This is from the brilliant woman who serves as secretary of the English department here and a life-long Korat resident.