My receiver shuts down frequently , wakes back after 2 or 3 sec .
do you have sufficient space around the unit? If it is in an enclosed space, has other components on top, etc, you may be overheating the receiver. Once it gets too hot it can potentially cause the issues you mention above.
If you have other components on top, try moving them to another shelf or below the receiver, and if you have a door on an entertainment center, leave the door open to help with air flow.