Couple of useful tips will help you avoid getting in trouble with other YouTubers and loose your reputation and channel. It is very easy and safe.
1. Do not use copyrighted content without knowing the law how to deal with it. You cannot avoid copyright notices, if you put the name of the author in the citation. The owner has to give written permission, and you have to have it to prove your rights.
2. Create your own content, that would be wonderful, and even in that case you can put Content ID claim your ownership and copyright the work. Well, this is easy to say, but hard work behind. It pays off though.
3. Use YouTube free audio library and / or videos in Creative Commons. Caution! Be careful: some videos marked or stored in the CC database are actually copyrighted material, or materials that violated the copyright. Even thought the source material may have been removed, you will still see videos in cc section. All of a sudden you get oops!
Unintentionally you are now in a bad situation! Your account is affected and it gets into Bad Standing.
4. How to detect the infringement, before it really affects your work?
When you want to remix a video in the Create -> Video Editor section, first play it and if you are using Chrome, right click on the video, copy the URL and paste in the next tab. After that open <show more> section and look at the attribution. By clicking to it, you will get more details about the video, its ownership.
Don’t get into trouble, keep up good work. The good news is that Copyright strikes expire in 6 months in case during that period you do not have any more strikes!
If you have additional comments, want to add something from your own experience, please share them here and we will consider.