[Magicality]

Unfortunately I don't have a Mogul to test it with...I am only monitoring the exchange server itself and can see the Touch is clearly not sending username & password along whenever the sync's fail...there will be no error displayed either (on the phone)...it does appear random to me as well (sometimes it will work fine for days then it will stop twice within a short time).

Most definitely the problem is somewhere with ActiveSync. Do you still have your Mogul? If so, would you be able to try and copy the ActiveSync.exe from the Mogul to the touch and see if you get the same behavior?