Most radio stations won't play on main user account

Question

Most radio stations won't play. In some instances double-clicking does nothing; other times, the name of the station appears, but nothing happens. When I use a different administrative account, these stations work just fine.
I've trashed and retrashed all the associated iTunes preferences, and have even done a complete deletion and re-install of iTunes (as per http://support.apple.com/kb/HT1224 ).
Thus it seems that the issue is with the account. But I don't know where to look to fix it, and I'm perplexed. Any suggestions? Thanks...

Answer 1

Back up all data before proceeding.
This procedure will unlock all your user files (not system files) and reset their ownership, permissions, and access controls to the default. If you've intentionally set special values for those attributes on any of your files, they will be reverted. In that case, either stop here, or be prepared to recreate the settings if necessary. Do so only after verifying that those settings didn't cause the problem. If none of this is meaningful to you, you don't need to worry about it, but you do need to follow the instructions below.
Start up in Recovery mode. When the OS X Utilities screen appears, select
          Utilities ▹ Terminal
from the menu bar. A Terminal window will open. In that window, type this:
res
Press the tab key. The partial command you typed will automatically be completed to this:
resetpassword
Press return. A Reset Password window will open. You’re not going to reset a password.
Select your startup volume ("Macintosh HD," unless you gave it a different name) if not already selected.
Select your username from the menu labeled Select the user account if not already selected.
Under Reset Home Directory Permissions and ACLs, click the Reset button.
Select
           ▹ Restart
from the menu bar.