I've just encountered this problem. Have owned a Pro-2 for a year now and only today the screen has started to go blank after a few seconds, requiring power cycle to bring it back, then it goes blank again. Changed screen-saver settings - nothing.
Then I remembered that last night I changed my default patch (by pressing Global twice). On the off-chance I chose a new default patch and the problem went away.
Will also keep an eye on it.