Currently Being ModeratedAug 21, 2013 11:12 AM (in response to sillina1)
I hope this answer will help if you are having the same problem.
Most times rebuffering stream appears when one is using a wireless network or has a problem with connectivity. A couple of tests can help root out the cause of the issue.
If possible, connect your laptop via an Ethernet cable and try playing again.
Check other websites to verify that your general connectivity is good.
Check that your modem is a newer model that support high speed and that the modem has the latest firmware applied from the manufacturer. If not, update the modem.
Internet Service Provider (ISP):
Check your ISP network speed at a site like http://www.dslreports.com. If possible upgrade your connection to a hgher speed with your ISP.
If using wifi, try clicking the option button on your wifi symbol in your Finder menubar
1. Select the Open Wireless Diagnostics...
2. Run the wizard to check your wifi network
3. If possible move your computer and wifi station into the same room
4. Note any differences in performance and try to reposition your wifi station so that it is not subject to blockages (attics and basements may not be the best locations).
All of these tests will help one to maximize the speed and performance of the computer / Internet.
I believe that as of version 10+ iTunes no longer offers a user interface to tune the amount of buffering one can use with the software.