A recording is known to exist, but is not circulating.
Very little is known about this four-track home recording. Cobain is believed to have been fleshing-out ideas for a new NIRVANA release, the arrangements having been described as similar to those of The Beatles' White Album. (1)
It was a loose jam with Kurt singing and playing drums, Pat on guitar and me attempting a lefty bass turned upside down,
Erlandson revealed in a Q&A on kittyradio.com. (2)
When asked whether he and Smear already had a point of reference or a demonstration of Do Re Mi, Erlandson responded, Yeah, Kurt had it already figured out, we were just there for the ride.
(1)