There's a few sample libraries around that are specialising in the 'atmosphere/drone/weird sound/fx' category like 'Atmosphere', 'Altered States', 'Morphology' etc.
The license agreements talk about these being licensed for 'musical compositions' usually with specific mention given to computer games where I guess the concern is that these samples will be used for 'sound effects' rather than 'music'.
Computer games often have these 'ambient beds' of noise in the background that may be interpreted as 'musical compositions' or 'sound effects' depending on your point of view (so do films and TV shows for that matter).
So, where does ambient sound effects / sound design (which is not allowed in the license agreements) end, and ambient musical composition (which is allowed as far as I can see) begin?
Is there a straightforward way to interpret these license agreements, so that it's easy for users to be sure they are within the license agreement, and don't have to be worried every time they use them in a vaguely 'ambient' context?