Comment 154 for bug 226279

@Richardg1952:

Look at your logs to see if you're not concerned by dhcp timeouts problems on network interface(s) if you've got them configured manually (or by a GUI != NM, using /etc/network/interfaces) and you're not using the first one.

If so, take a look at this:
https://bugs.launchpad.net/ubuntu/+source/pm-utils/+bug/236066