Why would anyone get in trouble?
Here's list of misunderstandings I've seen in people's responses.
1) We are good people and don't do it intentionally. Sadly, ignorance is not an acceptable legal excuse. I do believe that every artist here is an honest and upstanding person. And that's not being sarcastic. But I've seen my own work used without attribution or payment by even charities when if they had just contacted my office they could have probably used it for free. When confronted they almost always do two things: say they didn't know, which I can accept, and delete/take down/stop playing my works. The first is not an excuse but, generally speaking, if they do the second it shows some remorse. (I'd still prefer they pay me, but in spite of what some people might think, I'm really not a jerk, LOL).
2) It's not for profit. Doesn't matter. This might save you some grief but the copyright owner will have to sign off on it, and most, including myself, don't. It sets a bad example.
3) It only a small part/imprecise/distorted/sample. The Supreme Court is adjudicating or has recently adjudicated a case against music sampling. Think about that. A sample is a very tiny piece of music, usually used over and over, from somebody else work. The ones doing the sampling were sued and they lost in the two courts. I'm not sure of the outcome of the Supreme Court as I'm not sure they've made their determination. But it's not the size of part "borrowed." The key is if it's recognizable in any way AND/OR if it can be traced back to it's source.
4) It's for "personal" use. Yeah, but you had to get it from somewhere, right? That a violation of distribution copyright. And/or reproduction copyright. Or even application. The point is, even if you do it on a very, very small scale, you may be violating the artists rights. Think about it, if everybody made a copy of some song only for "personal use" wouldn't it potentially be a loss of, well, a LOT of money?
5) We didn't make money or intend to make money off it's use. No, but the artist made it to make money and by using it you are depriving them of potential profits. I once wrote a program that went viral before viral was a word. Early 1980s graphics and all. I watched as thousands of students at my college copied it and "shared" it with each other. It went around the world and twenty years later I found from a Russian student that they even played it in the Soviet Union! After trying to get paid for two years and spending more money on lawyers than I ever made on the game, I gave up and let it go. I once sat down and figured out that, even without the lawyers, I made about 52 cents an hour for my work. Sigh. But of course if you don't sell it, but just pass it along, you aren't getting paid so why should the artist?
So there are 5 misconceptions about copyrights.
Finally, just to be clear. I have no desire/intention or anything else to get anybody in trouble and even if I knew somebody did violate some copyright law, I wouldn't report them as it's just to minor here. But that's because I'm no longer a part of the WIPO or any other software copyright protection agency, and I can tell you there are people who will, should you be caught. Usually they threaten and if you pay them a "fine" they let the matter drop -- it's usually a scam, but since you are in violation of the copyright, do you want to pay them a small fee to go away or take the chance it's not a scam and have to go to court?
In the end all I'm saying is, "be careful" and do as Sir Squirrel does, check and check again.
AJ