Please issue the below command to find out which sub-interface of your NIC card needs an adjustment of MTU value:
sudo /sbin/ifconfig
Now, suppose the interface is PPP0, then issue
sudo /sbin/ifconfig ppp0 mtu 1300
If it is PPP1, then replace ppp0 to ppp1 in the above command.
To make the changes permanent:
sudo nano /etc/ppp/ip-up
/sbin/ifconfig ppp0 mtu 1300
Save the file.
Now you should be able to browse anonymously without any interruptions!!