Until you get the kit, make sure you don't shut it off until you get it to your parking spot!
Bruce, Go to your dealer and tell them you want the "kit" for the PTO. It will come with a new PTO switch and a small harness modification which has a diode? installed which prevents electrical feedback to the PTO switch. It should be free. It wasn't until I paid my dealer to install a new switch, then my friend who has an identical mower started having the same problem. He took his in too and 50.00 in labor and the new kit later he's off and running. I picked up my kit from the dealer about 2 months ago and I have not yet installed it but, I will have to very soon since it is starting to act this way again!