I have since fixed the creaking. It ended up being at the seat/seat post area. Just a little tightening and all was fixed. This is a different bike than the one that has the chain slip.

The bike that had the crank problem with has now started creaking on the pedal. I am assuming it is the cleat rubbing against the pedal. I have heard this can be fixed by applying paraffin wax on the cleat and/or pedal, but I have yet to try this.