Export thread

I have a husqvarna z 254f zero turn mower with 80 hrs on it. Last time mowing, I noticed the throttle would decrease while mowing and I would have to move lever back up to full throttle every so often. What is causing this and is it easy to fix?

Thanks

SO the lever itself is moving >
If this is the case get under it and tighten the bolt 1/4 turn.
Easier said than done on a ZTR