Comment 49 for bug 1292830

Solution found the problem is an old one form previous versions.
The problem is graphic card driver related in particular NVIDIA.

The solution is simple:

In terminal as root:

cd /etc/pm/sleep.d/

$: touch compiz-fix.sh

$: nano compiz-fix.sh

#!/bin/bash
setsid compiz --replace

exit 0

ctrl+x to save

$: chmod +x compiz-fix.sh

to remove the changes just do as root:

$: rm compiz-fix.sh

Worked as a charm for me!