I'll cut right to the chase here...the sort of music in "At Home" is very dated and I cannot imagine many folks enjoying it today...let alone back in 1939! Mr. and Mrs. Crawford are both organists who play together on separate organs. Technically, this is impressive but their versions of "Tea for Two", "The Very Thought of You" and the hellishly awful "I Love You Truly" are far from the best versions of these popular tunes of the day and reminds you of an old fashioned roller rink with its organ!
IMDb points out that Mrs. Crawford says nothing and her husband speaks only a tiny bit. The rest is handled by Percy Helton (a VERY familiar actor in the 50s and 60s on TV and in films) and Anthony Ross. The plot, such as it is, consists of Helton coming to the residence where everyone is waiting for a prospective sponsor to arrive so they can pitch him a radio program...and they mistake Helton for this man.
By the way, if this was supposed to be for a radio program, why was one of the acts a dance team?!!?!? No one could have known there were dancers dancing when they performed!!
Overall, technically well made but a film many will have extreme difficulty finishing.