Sound when pedalling
Maximum down position is odd - that's when the power stroke is over so its not the pressure causing your noise.  Did you assemble it yourself?  Could be a loose pedal, or a pedal bearing needing lube.

Try popping the chain off the chainwheel and pretend to pedal.  See if the noise still exists.  If yes then its not your chain.

Finally - since your bike is new, have you taken it back to the shop for a tune up?  Almost all bike shops offer a tune after 6-12 weeks to fix up cable stretch issues etc.  A minor creak like this should be covered by that, or by warrranty.