Bad Soundquality after installing ServicePack2 (SP2) for Window XP, especially with PPP and VPN connections (kb2847)

The information in this article applies to:

  • Microsoft Windows XP Professional
  • SwyxIt! all versions
  • SwyxWare all versions

[ Symptoms | Cause | Resolution | Status | Links ]


After the installation of service pack 2 for Windows XP the audio quality of calls via SwyxIt! is very bad, especially with PPP and VPN connections. Also using UMTS cards causes broken or no audio streams at all.


Unfortunately Microsoft introduced a bug with Service Pack 2 for Windows XP regarding the handling of audio pakets, which should be transmitted and received with quality of service (QoS). Versions of Windows XP older than Service Pack 2 are not affected.


Microsoft offers a workaround and a hotfix for the above problem. More details can be found inside the Microsoft KB Swyx recommends to install the Microsoft hotfix on systems experiencing this problem. The hotfix can be requested at Microsoft free of charge via the support addresses of Microsoft mentioned inside the KB article. For the English and German versions of Windows XP Professional SP2 you can download the Microsoft hotfix via the links at the bottom of this article.


Has been fixed with new version.


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