I have a XL 310 (It says Canada). We can not get the device to turn on once we have used the unit. The screen shows that the device is going to be put in the briefcase and turns off. We will try to reactivate (turn unit on) and can not bot the screen to activate. We hold the power button down for 2 to 3 seconds and the screen activates and then goes to a faint light and a pop (very low) comes from the speaker. If I keep working with it 20 to 30 minutes I can finally get it to function. Anyone had this problem and what do you do to fix it?