I find this problem intriguing, because I've listened to a couple of sound samples of Mississippi John Hurt singing MOANING THE BLUES, and I find his words totally unintelligible.

There seem to be lots of songs out there called MOANING THE BLUES (sometimes spelled MOANIN') also MOANING BLUES, DEEP MOANING BLUES, MOANING AND GROANING BLUES, AWFUL MOANING BLUES. If you consider that MOANING is awfully close – in meaning, pronunciation, and etymology – to MOURNING, which can sound like MORNING – then there's a whole host of other songs that might be related.

I've listened to several of them – as sound samples, anyway – but none that I've heard throw any light on what MJH is singing, or even seem like the same song.

Songs called MOANING THE BLUES or MOANIN' THE BLUES have been recorded by Blind Blake, Memphis Minnie, Allen Shaw, Charlie Spand, Victoria Spivey, Pigmeat Terry, and Henry Allen. A song with that name was written and recorded by Hank Williams, and covered by Merle Haggard, Marty Robbins, and Mel Tillis.

Songs called MOANIN' BLUES have been recorded by John Lee Hooker, Lightnin' Hopkins.

DEEP MOANING BLUES was recorded by Ma Rainey.