I know someone will know the answer

[Michael Bush]

It's like when they first put tomato juice in glass jars instead of cans.  People were used to tasting the metallic flavor of the can so they thought it didn't taste right.  So they added the metal flavor to the juice and then people would buy it.

You have honey that tastes like honey instead of the overheated, metallic flavored honey they sell in the grocery store... yes, you can make yours taste that bad...

[jsmob]

I lived in a duplex that had a huge Privet bush in the yard. The bees honey tasted like privet that year.
Not a good taste.
The next year we had moved into a house just 4 doors down from our duplex. The honey that year, and then on, has been great.
I would say that it is most likely the source of nectar and not your extracting. The wax doesn't really have a taste, dose it?
But taking the honey early or later might be the thing to do.

[Brian D. Bray]

Timing of your harvest can be critical to the taste of the honey, ie after the blackberries but before the knotweed. 
Some honey sources, in large enough quantity, can make the honey taste like damp socks, not so good.

I use a cider press to crush and strain.  I load the combs cut out of the frames into a pillowcase, place it in the hopper and tighten down the ram.  All of the honey is forced out of the combs through the pillowcase (use a clean one please) and then through a strainer(s) into the storage containers.  The only time I heat my honey is to reliquify it, and then by placing it in hot tap water and letting it set, sometimes I have to use more than one tap water treatment to completely reliquify it.
A small film of wax and pollen on the top of the honey is a good thing and should be restirred into the used upon each use.