Dear Stccmc,
I’ve moved your post because I thought it would match better to here than to the clicking noise; really hope you don’t mind.
Of course there are also other posts which will belong to your question,
some of them are linked below.
So you’ve ridden about 1440 km in sum, I mean that could be enough to kill the pads.
Yes, I believe indeed that wear (and misalignment of both pads, also caused by wear) may produce noise.
That’s easy; unmount the brake caliper, it’s just two bolts 
Ok, next try serious:
First, you might answer yourself the following question:
How many times, so far, did you readjust your brake cable or the pads itself?
(One or two times can’t mean wear, but several times would be a sign of wearout, I’d say.)
Please note that there are two types of brake calipers on the market;
on the older, rounder ones you can look at the pads from the underside of your bike.
Do yours look like these:
COLORED BREAK SET
or do you have the older version?
I’m asking because we didn’t check by now if the new calipers are using the same pads as the old ones.
If they do - hopefully - then you might try another type of pad in correct size,
please refer here for alternative pads:
Re: Disc brake caliper lever bumps into caliper body
(I’m sure to have a pair new calipers at home, but I can’t find them at the moment to compare, sorry 
)