Midi Express Usb And Shutdown, It won't let my Mac rest! Options

[cornutt]

Has anyone else run into this? I just acquired an MOTU MIDI Express XT USB (replacing an older unit that used a serial port). I'm running 10.2.4 on a DP G4. I have configured my USB with the XT plugged direct into one of the two ports on the G4, and an Epson C80 direct into the other. My keyboard, mouse, and floppy drive go into a Belkin self-powered hub which in turn is plugged into one of the ports on the back of my Studio Display.

What I find is that with the XT switched off, the Mac can't shut down! If I tell it to, it goes through the shutdown cycle, there is a momentary change in fan speed, and then it comes right back up. Worse, if everything is shut down, and there is a power failure, when the power is restored the Mac will start up by itself. (In the past week we've had thunderstorms, and I've had to get out of bed in the middle of the night twice to shut it down.) The only way I can make it shut down, short of yanking the power cord, is to either (1) hold down the power button as it's trying to start back up, or (2) switch the XT on. If the XT is on, the shutdown works normally.

But I don't want to have to leave the XT on all the time. Some Usenet posts I've seen suggest that it might be a problem with the amount of current being drawn off the USB bus, but why would the XT -- a self-powered device -- be drawing current from the USB when it's switched off? I'm thinking about buying another hub and running the XT through that to see if it makes any difference. Ideas?

[jim_h]

Thanks for the tip about the hub, I'll check it out.