I have a 2004 Lazer Z HP with a 48" inch deck (three blades) and have had nothing but an excellent experience up until recently. Starting a couple of weeks ago, I noticed the machine was not cutting as good as it had in the past. It is to the point now where it is leaving a small strip between the blades and a pretty uneven cut elsewhere. I have done the following but have yet to correct the problem: removed the striping roller, replaced the blades, made sure the deck is level and checked to see if any of the housings are loose. Any suggestions?