I only get audio on TV when using iTunes, no audio on Safari. Any ideas?

I have a Macbook Air. I bought an Apple TV a few days ago. It seemed to work fine on the first day but now I'm having problems:

It is fine with iTunes - I can play music and choose whether the audio comes out of the laptop speakers or the TV speakers.

But when I try to use Apple TV to show/listen what is on my laptop I cannot get the audio to come out of the TV speakers. For example when I run the BBC website and play a video I can saw th video on the TV ok but no audio - I can only hear it when I select the laptop's built in speakers. Also when I try to switch from laptop to TV speakers the video sometimes freezes. It's all a bit odd.

Thanks, Simon

The various TV channels and videos that come with the Apple TV seem to work fine i.e. they play with video and audio perfectly. Its just when I try to play videos from websites under Safari when I can't get the audio out of the TV speakers.

Since axing the question I discovered some other conversations and it seems like several people were having a similar problem when using Safari. I have downloaded Firefox and it works perfectly. I would still like to know what I can do to make the audio work properly with Safari because I am sure it worked a few days ago when I first got Apple TV - I think I must have changed some setting somewhere without realising it.

Thanks. Are there any settings somewhere I could check? I'm not much of an IT guy I'm afraid. For some reason Firefox, iTunes work ok, but Safari doesn't. I can get audio out of the computer speakers but when i select Output to be on TV no audio comes out and quite often the video stops.

I appreciate your help, Vazandrew

Hey vazandrew you are a genius! I shutdown and restarted my Macbook and Safari works just fine! Most odd.

I appreciate your help, thanks so much!

Simon