The problem is that the drivers for the OuickCam Proo 5000 mic screws up the drivers for your audio card. I have this same problem, but I can't find a working fix for it anywhere.
They may need to increase the mic volume in the sound settings, and even better if they are using a laptop it may well have mic boost in the settings. Tell them also to make sure they set the cam up in the relevant im programme they are using.
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