2002 Honda Civic Whining sound that comes and goes

Noises problem
2002 Honda Civic 4 cyl Front Wheel Drive Manual 100k miles

My civic has been making this whining sound that comes and goes but is there more than its not. I do not have a lose in power at all and my string does not seem to be affected. So when I went to take a look at this I saw the main belt was moving just fine. As I was doing this the sound was coming and going. Then when there was no sound I looked below the main belt and saw another belt that was moving, but when the sound came back this belt would stop, then when the belt would move the sound went away. All this time my car was just sitting in my driveway with no one touching anything. So what I want to know is this the timing belt or some other belt and what needs to be done?