If this problem just popped up on you and did not appear upon installation then look to your NETSTAT command in terminal.  On my machine this is caused by hackers attempting to cause a problem.  The terminal command for this is netstat --inet -an.  See if you get something that looks like mine.

ric@ric-desktop:~$ netstat --inet -an
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State      
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN     
tcp        0      0 192.168.1.100:42908     72.14.204.19:80         ESTABLISHED
tcp        0      0 192.168.1.100:60936     64.233.169.166:443      ESTABLISHED
tcp        0      0 192.168.1.100:37803     91.189.89.222:443       ESTABLISHED
tcp        0      0 192.168.1.100:50939     91.189.89.225:443       ESTABLISHED
tcp        0      0 192.168.1.100:36574     64.233.169.103:443      ESTABLISHED
tcp        0      0 192.168.1.100:38757     64.233.169.138:80       ESTABLISHED
tcp        0      0 192.168.1.100:44665     72.14.204.19:443        ESTABLISHED
tcp        0      0 192.168.1.100:39014     173.194.4.20:80         ESTABLISHED
tcp        0      0 192.168.1.100:44669     72.14.204.19:443        ESTABLISHED
tcp        0      0 192.168.1.100:40278     74.125.115.97:443       ESTABLISHED
tcp        0      0 192.168.1.100:50935     91.189.89.225:443       ESTABLISHED
tcp        0      0 192.168.1.100:37806     91.189.89.222:443       ESTABLISHED
tcp        0      0 192.168.1.100:54105     74.125.113.132:443      ESTABLISHED
tcp        0      0 192.168.1.100:50938     91.189.89.225:443       ESTABLISHED
tcp        0      0 192.168.1.100:44672     72.14.204.19:443        ESTABLISHED
tcp        0      0 192.168.1.100:44673     72.14.204.19:443        ESTABLISHED
tcp        0      0 192.168.1.100:44666     72.14.204.19:443        ESTABLISHED
tcp        0      0 192.168.1.100:55331     64.233.169.103:80       ESTABLISHED
tcp        0      0 192.168.1.100:57620     72.14.204.189:443       ESTABLISHED
tcp        0      0 192.168.1.100:37805     91.189.89.222:443       ESTABLISHED
tcp        0      0 192.168.1.100:36569     64.233.169.103:443      ESTABLISHED
tcp        0      0 192.168.1.100:44667     72.14.204.19:443        ESTABLISHED
udp        0      0 0.0.0.0:5353            0.0.0.0:*                          
udp        0      0 0.0.0.0:34228           0.0.0.0:*                          
udp        0      0 0.0.0.0:68              0.0.0.0:*                          


I am having big hacker issues.  The Canonical Addresses are not Canonical trying to help me out. I have much data on this crew. They are on me 24/7 trying to keep me from gathering data on them.   Anyone wants to know exactly what is going on can contact me at <email address hidden>. The object of their activities is to cause computer replacement.  If your computer is over 2 years old is their guideline.  
these guys can ghost a network in nothing flat.  Primarily they work Windows OS, but in my case they have learned to do Linux.  They walk through Firefox security like it is nothing.
So look to your NETSTAT in terminal before blaming Ubuntu.  The actual bug is in the CMOS, but you may not be able to replace the CMOS even though it looked like you did.

Happy computing ya'll.

ricyaun