USB stability problems, especially with Windows XP (kb2620)

The information in this article applies to:

  • SwyxIt! Handset P250
  • SwyxIt! Headset H320 (monaural)
  • SwyxIt! Handset P220 (USB)
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Home Edition
  • Microsoft Windows 2000 Professional
  • SwyxIt! all versions

[ Information ]


Especially in the last few weeks and months, more and more problems with USB-devices get reported, especially under Windows XP.

Nowadays some information was available from Microsoft regarding these problems, and it seems that especially USB audio devices can make trouble, because they use a different transmission format than most other USB devices. The use of so-called "isosynchronous highspeed-devices" could here lead to the problem that the CPU was used at a level of about 80% without any idea, where all this power was going. Also, errors in the transmitted data occurred, which leads to crackling sound or short interruption of the voice datastream.

Microsoft has released a patch for Windows XP SP1, that addresses some of these problems. The patch can be received in the automatic updates, or it can be downloaded directly from Microsoft. The name of the patch is a bit irritating though, it may give users the impression that it is not really important! The name of the MS knowledgebase article is "Availability of the Windows XP SP1 USB 1.1 and 2.0 Update", it can be accessed with this URL:;en;822603

Regreatfully, practical experience shows that the patch alone can't help in many cases. The USB controller chips which are implemented on the mainboard itself seem to prove unstable or unreliable, especially under Windows XP. We would like to create a list with the experiences of our customers, which mainboards and USB controller chips proved themselves to make problems, especially after an upgrade from Windows 2000 or earlier to Windows XP. Feedback with informations like this would be highly appreciated. We had some mainboards ourselves that were used without problems under Windows 2000 - When we changed to Windows XP though, the built-in USB ports became unusable for audio devices.

With some machines, the easiest and quite inexpensive solution was, to simply install additional USB controller cards. Eventually, this saves a lot of time that would otherwise be spent for troubleshooting, so that the about 20 euros for the additional card can be easily justified. Please note: There are of course add-on cards, which use exactly the chips that lead to trouble, especially with Windows XP!

In our lab and also in our normal office we tested add-on cards with VIA-, ALI- and OPTI-chips. Only the cards with the ALI M5273 were found to be reliable in the mainboards that we had in use in these computers - They made no problems whatsoever, in the tests and also in normal use. Also found to be working properly are addon-cards based on Intel-USB chips, although this was not tested in our lab but reported to us. These seem to be working fine under Windows XP as well.

As a conclusion, the follwing can be said.

If USB audio devices are used, the following requirements MUST be met:

  • If the mainboard uses a VIA chipset, the newest VIA system driver package (4in1, hyperion, or whatever the next name may be) must be installed.
  • If you get problems with the built-in VIA USB ports, it might be inevitable to install an addon-card.
  • If you install an addon-USB controller, always make sure that the chip used on it is positively tested.
  • In WIndows XP, always install the mentioned patch, additionally to service pack 1.
  • In the energy options of all the USB root hubs in Windows XP, please always disable "Windows can disable devices to save energy"

With respect to all the experiences gathered in this field, there's a necessary addition to the article: It is for sure still possible to find new hardware combinations that don't work properly. The list, that will be created in this article and that will grow, also with the help of our customers, can't be understood as a guarantee. We can only list the experiences of ourselves and of our customers, positive and negative ones - And thus hopefully minimize the risk of buying unsuitable hardware components on your side.



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