The Warner Bros. Music Show was a series of releases sent to radio stations for broadcast between 1979 and 1988 – they weren’t ever really intended to be released to consumers, but because they were distributed on vinyl they show up in vintage stores from time to time. I was not hip enough (as a nine year old) to be listening for a Talking Heads live show in 1979 but it is a great show.
They were recorded live at the Agora in Cleveland on December 18, 1978 – there are lots of bootlegs of that show, some under the title Electricity.
Per Discogs there’s some controversy about whether this is a counterfeit pressing of that promo release