I recently purchased a Toro 20332 recycler and used it on a few lawns so far. Mower has been working great, except once in awhile the rear drive just stops. I disengage the personal pace drive and roll the mower ahead and then back. When I engage the drive again, away it goes, no problem. Happened about 10 times today on a 1/3 acre lot. I did notice it happening more when bagging. Any idea what can be causing this? I'll be talking to my Toro rep, but I thought I would start here first. Thanks!