Flashing a toothless smile, 96-year-old Gaew breaks into the jaunty, staccato verses of "Mo Lam," a style of folk music that reaches deep into the cultural heritage of northeastern Thailand.

For generations, the humor-laden lyrics have covered tales of unrequited love, rural hardship and changing political winds, with the traveling Mo Lam - the name also refers to the music's expert singers - commissioned to spread campaign messages across the remote villages of the Isaan region.

But the politics has for now been pulled from the playbooks under a military government which brooks no dissent - especially from Isaan, the heartland of the "Red Shirt" movement loyal to the elected government toppled by the generals in May, 2014.

"Mo Lam is our history, our culture," says the remarkably spry Gaew Sornthunthue.

The male or female Mo Lam delivers the song in the Isaan dialect to the mesmeric tempo of a "kaen," a bamboo mouth organ unique to the Thai northeast and neighboring Laos.

Gaew's early memories of the music stretch back to the start of the 20th century when Thailand was ruled by an absolute monarch, and Isaan's Laos-origin people were still yet to be fully co-opted by the central state run by Bangkok.

To Isaan people, millions of whom now live and work in Bangkok, its sound still evokes nostalgia for a region which is modernizing at breakneck speed but maintains a proud and distinct culture.

"We use Mo Lam to talk, debate, express ourselves and reflect on our lives and traditions," says Sarawoot Srihakot, a kaen player and music teacher trying to preserve the art form.