mach 460 stereo cuts off

Take a nice firearm to your Mach 460 system. I hate mine!!!!!! The bass has been completely out on mine for a week. The CD-changer rarely works right. Everything about it is crap.

hopefully someone will be more helpful than me

The Mach 460 system wasn't very good right from the beginning. Some even have an intermittent buzz whose frequency runs with the engine RPM.

Ford says check grounds. I found a loose ground in the underdash area just ahead of the shifter and that stopped my buzzing problem.

That may be part of your problem too.

(Make sure the ground that goes to the hood from the firewall/fender is connected and making a good ground.) Some guys have the hood off or change hoods and don't remember to put that one back on. It's important.