My belt broke clean across if you recall at about 12,000 miles.
I believe it might have been attributed to trying too many concoctions on it, to get it to quite down.
I believe any kind of lubricant contributes to premature weakening.
I think the noise is mostly associated with a unbalanced belt....
By this I mean if you have more belt or distance (teeth) on the top, from where it leaves the rear pulley, to the front pulley, than from where it leaves the front pulley to the rear.....
Then you will get a noise as the belt will load up that "slack", be it ever so slight, at the front pulley on top where it enters the front pulley.
It will try to dissipate this preloading by moving quickly from side to side, creating a chirp, or push on the pulley teeth, trying to ride up on it like it wants to "push out" and that creates the whine.
I notice, as others have spoken to, weather, temp, humidity, etc, plays a factor, but when the belt is just right, you will notice a nice humming.

I believe the best thing is to just keep your belt and pulleys clean, by brushing them as you do your teeth in your mouth, often, but not twice a day  

The belt Dave provided for me is working great. I tune mine by ear, once when the weather warms, once when it cools, and just ignore any noise between  

You think Suzuki spent ANY R&D money on the harmonics of this bike?  

Raydawg you have hit the nail squarely on the head. Suzuki see this as an entry level motorcycle and nothing more. That's why they have never bothered addressing the camchain tensioner problem - it is probably on its second or third owner before it becomes an issue and in a lot of cases it doesn't become a problem for many years if the bike doesn't doesn't get used much! However, having said that, you can go on any other dedicated motorcycle forum and you will find that they all have their foibles! I thought the Suzuki GS500 was the most bullet proof motorcycle ever made (well mine was) until I went onto the forum!.