> Then I end up with several of the same characters in a row. 

The typing style for low profile keyboards is different to your old keyboard. 
You are not meant to rest your hands/fingers on the keyboard and then jump on
the keys as if it were a mechanical typewriter.  Instead your fingers are
meant to float over it.

However, what you're describing is key switch chatter.  Mechanical keyboard
switches can suffer from this problem.  You depress a key once and once only,
but it registers multiple inputs.  It can be *very* annoying!  There are some
fixes for mechanical gaming keyboards, but if you have a new keyboard you'd be
better off asking to RMA it.