Gunmen of the Apocalypse - S6-E3
Visible crew/equipment: Just after the simulant beams aboard and Lister and the Cat sit up from the table, a boom mic can be seen at the top of the screen. (00:07:40)
Gunmen of the Apocalypse - S6-E3
Continuity mistake: When Lister says the escape pod is not an option, his hands are apart in front of him. In the next shot, they are together. (00:12:20)
Answer: The cello is a large four-stringed instrument, which, when it is played, stands vertically on the floor between the player's legs (assuming they are seated). If it is to grow as large as the other instuments mentioned will, it would require a rather unseemly lack of femininity to be able to encompass it with the legs.
Rooster of Doom