Audio Gain tool not working

[default79hprwqji65u]

I have tried to use the Audio Gain adjustment tool to normalize the audio on my video.  When I try to use it I get an error message "clip gain not responding."  Does anybody know what is causing this and how to fix it?

[Steve Grisetti]

Is it only this clip that is giving the program an issue or does it fail with any clip? If you add an MP3 to your project, does Normalize work on it?