The MotU MTP/AV-USB also causes this problem. I fixed it by putting a powered hub between the Mac and the MTP and leaving the hub on all the time. Richard M. Kriss wrote: > Ramsey, > > Your tip made me thing and the problem (restarts after a shut down) may be > caused by the flakey Integra USB to Serial adapter I have plugged into one > of the USB ports. > > I will try removing the adapter before trying the shut down tonight. > > The only fix I have found that really works is to remember to pull the power > plug after the 'Shut down' does it thing and before the G4 restarts on it > own. >