Ok i have never had any problems with my walker until last year when it started leaving a very small but noticable line of grass uncut in the center of the deck. The grass is normal height, i have not hit anything that i know of, and last year i ended up having to buy a new deck which fixed the problem. Now it is doing the same thing, and i am wondering if anyone can help me figure out what this problem could be. The dealer says i am the only person he has ssen have this problem! HELP!!!