If the rhythm is uneven, and especially if the rhythm per crank rev is different on different chainrings then it's the chain. If it's a more even rhythm or constant it's the pulleys. Some lubes are not good at keeping out water, and the chain can squeak even if it appears to be lubricated. I don't know about the current formulation, but many years ago Triflow was well-known for that behavior. If you determine the noise is in the chain and lubrication does not resolve it you need to either remove and totally clean it in solvent, or if unable to do so spray it with WD-40 and then re-lube.
Last edited by cny-bikeman; 03-10-14 at 09:03 AM.