Mic works no Audio in iChat

With Logitech ClearChat wireless headset connected and selected in Sys Prefs/Sound/In & /Out and selected in iChat/Preferences/Video the Mic works with iChat but no audio from earpieces other than alerts.
Sound is Ok with iTunes and headset works well in Skype.
Where else can i check for sorting this issue?

2.4 GHz iMac 10.6.3 and downloaded and installed Logitech update.

I had this problem with a previous version of that headset and finally got it working. Once I did it worked about as well with iChat as it does with Skype. That's the good news. The bad news is I am not entirely sure what I did.

I think you are on the right track with the system settings. It took me a while to figure out that the iChat settings were somewhat independent of the system settings. Try the following:

In System preferences switch the sound to something other than the headset. Now do something that should lead to noise (such as opening a movie to see if you get sound. If you do now switch back to the headset in System Preferences and see if it works in iChat. Sometimes I think the wsetting doesn'tstick from time to time.

It is now working - what did i do?
The only step that seems relevant to me is that in iChat/Preferences/Video is that i selected Sound output; Wireless Headset.
before i selected Microphone: Wireless Headset.
Each other time i had worked down the list starting with the Microphone.
If the reasoning becomes any clearer i will post further.

Seems to be the trick - first time up make sure Nbr 1 is selected to headset before Nbr 2 if you are using iChat - Skype is not that picky;


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Reason why? - i have no idea!!

Update - seems with Headset and Quick Time and uTube it is just a matter of plugging in Transmitter and headset is go, however as usual, iChat is more picky. If you plug in USB transmitter and then turn on headset there is no sound output in headset but mic works - it will work if both sound output and mic are reselected but only if sound output selection precedes mic. So with iChat a simpler way; turn on headset then plug in USB transmitter.