Loose chain-ring bolts are an oft overlooked culprit. They're also the easiest to tighten, since you don't have to remove the crank or pedals, so it's worth a shot. Check that they are tightened to the proper torque. 

Why does my bike make a noise when I pedal hard?
I am trying to use VBA to automate the Change Picture function when you right click a Shape in Excel/Word/Powerpoint.

However, I am not able to find any reference, can you assist?
