I thought I noticed last Fall leaving some higher areas of grass while 95% cuts even as new. I have 250 hrs. On with original blades sharpening once a year (50 hours). Mowing the other day it seemed to be the same. I put new blades on yesterday but it still is not as even a cut as before. Some cut paths have a slightly taller row of grass. The deck measures the same height on sides and front from the ground..It cuts the same regardless of height but appears better cutting shorter. Advice welcome.