Riding Lawn Mowers

*Severe itching due to mower vibration* I just purchased a YTH24V48 Fast Tractor lawn tractor with the 48" cutting deck a few months ago. While I have no problems mowing with it and find it to be quite comfortable, my daughter has used it and complains that the vibration causes severe, unbearable itching around her midsection and thighs. This happens consistently within five minutes, regardless of the mowing blades being on or off. Has anyone else experienced this problem? Thanks.
-Fred