I am not a Dell Employee
Dell forum member since 2002
Home Built PC with Gigabyte GA-Z77X-UD5H motherboard, i7 3770 CPU, Windows 7 64 bit Home/Win 8.1. SSD drive. Sonar X3c 64 bit Recordng Software.
Member of Nashville based R.O.P.E.
An audio codec is a computer program that compresses/decompress digital audio data according to the given audio file format or streaming audio format. Most codecs are implemented as librares which interface to one or more multimedia players, such as XMMS, Winamp or Windows Media Palyer.
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So he could be hinting that your Skype program may be having a codec issue or missing something. I know when I've downloaded some movies that were compressed using Divx I had to install the Divx codec in order to properly play them.
I know in the old days after installing the latest and greatest DirectX drivers that sometimes it would cause issues with a sound card and I would have to reinstall the sound driver. I know you said you've done that part already but I'm just putting out some information for ya.