The Security Event Log [Vista Ultimate] is filling with entries advising the following: Code integrity determined that the image hash of a file is not valid. The file could be corrupt due to unauthorized modification or the invalid hash could indicate a potential disk device error. File Name:\Device\HarddiskVolume1\Windows\System32\stapo.dll I have uninstalled/reinstalled the current SigmaTel Audio drivers several times with no effect. I sincerely doubt it is a disk problem, but more like to believe it is a Vista anomaly. Any thoughts?