According to info on cc license the audio file is licensed under the cc license it used when it was downloaded. Now heres the thing, one of the samples i have downloaded has changed its license to cc-by-nc. It was under sampling+ when i downloaded it.
So, how do i prove this to people such as the uploader, youtube etc if i use it commercially under the sampling+ license. I have decided not to use it till this is cleared up.
I dislike this option that people have to add restrictions after thousands of people downloaded it when it was freely usable in any project.
This is a difficult one, and we discussed this quite a bit... You can obviously use the sample under the original license, as you downloaded it under that license.
Nothing stops an author from changing a license of a sample - it is HIS sample, he can do whatever (s)he wants with it. But nothing stops you from using it under the first license it was released under.
You would need to have something like a license history on the sample's page. But it needs to be clear that who downloads it now, can't cheat and say they downloaded it 5 months ago, when it was still under a different license.