Help with reading the items? Maybe the dumbest question ever.

Hey everyone, been having this problem for a while, and the annoyance
of it has kept me from giving Reader much of a look to compare with
other feed readers. Anyway...

Sometimes when I scroll down each item in the lens (using the 'n'
keyboard shortcut), the reader automatically gets populated with the
content of that item. This Is A Good Thing.

Sometimes, however (like today, when I finally got fed up with it
enough to post here), I have to hit <ENTER> on my keyboard every single
time to make the content of each item appear. This Is A Hassle.

Little help please?

Cheers,
Stu