Hello gamedevs!

I’ve been making games as a hobby for some time. For assets, I would usually just rip whatever I found would fit best from the internet and edit it afterwards.

Now this is great (I think)for personal projects and the likes. But when you want to make them public that’s not possible so whenever I’m building something for a public (free or paid) I make everything by myself or I use CC0 assets (or CC-BY with attributions in credits).

One thing I wondered is how much can I straight up use a sound effect without problems?

I have multiple scenarios:

Scenario a

I rip 1 to 2 seconds from a music. Apply some effects (reverb and filters for exemple) and add another sound on top of it. Would it be problematic to sell a game with this?

Scenario b

I record/rip a sound from a game, maybe I apply an effect on top of it then dump it into my game. Would it be problematic to sell a game with this?

Scenario c

I record a part of a music (like scen. A) and I merge it with 5 other sounds. I then apply a lot of filters and then, when in game, the sound is played through audio alteration functions using player inputs and game state as parameters. The original sound would not be recognizable. Would it be problematic to sell a game with this?

The grand question here is how much of an art piece has to be destroyed when building on top of it for it to be deemed original or something. But that’s not the question of this post.

Thank you for reading this ^^

Hope some of you can answer this or give some guidance.

PS: I really don’t mind giving attributions, in fact I really like being able to redirect to skilled artist through my work. I don’t want to avoid doing it, I want to know the legal troubles of using samples from found audio.