Greg makes a solid point - and I'd look to it as the culprit first.
However, if you play a round, and suffer the same problem, it's your equipment.
Trivia time:
What is the tolerance for loft and lie between
clubs of all manufactuers - OEM or component (save the Ashton E3)?
+/- 1°
Now, you say, what difference does 1° make?
Well, at the longer
clubs, the loft spacing often looks like this: 24° 4 iron, 28° 5 iron, 32° 6 iron. Now, if the 6 iron is -1°, and the 5 iron is +1°, now the lofts are 29° and 31°, respectively. And they hit close together. The other factor is that even though the tolerances are +/-1°, out-of-spec heads still get out there. So you might even have both a 5 and 6 iron at 30°.