I've been having an issue with my bike where there is a constant creak on each stroke of the crank, which appears to be at the same point in the stroke. I've replaced the bottom bracket, replaced the pedals, checked the chainring bolts are tightened, checked derailleur alignment and ensured the crank is secure in the bottom bracket but the noise still persists. Any idea what could be causing it or you would be able to help out with it, please? Thank you, George