This is second year with this mower. I use it for some steep stuff mostly. But, it does not matter if I am on level ground or hillside, it always leaves blades of grass here and there. It does this on dry grass. I put new blades on it and it did not help. I use the mulch plug mainly. I have noticed that it does much better with the bag on it, but that slows me way down. And I noticed that it does much better when I set the deck below 3", but I am cutting fescue mostly fescue and try to stay at 3 or better. I read somewhere that the the deck lost its vacuum power when it was raised above 3" - but if that is true then its not very useful. I'm tired of having to walk all the place to trim ONE blade of grass. Anyone got any ideas on how to fix this?