If you're in the smallest front chainring (1), chain noise as you move over to the middle or further on the rear cogs is to be expected from cross-chaining. Try riding with the chain on the middle front chainring most of the time. Shift on the smallest chainring only for going up hills.
Your rear and/or front derailleurs may need to be adjusted, too.
Do it yourself with the help of Park Tool http://www.parktool.com/blog/repair-...illeur-systems
Or take it to a bike shop.