12 Jun
2010
12 Jun
'10
2:34 p.m.
Hello all,
Does anybody know if there is any relationship between the Intel Rate
Matching Hub
(http://www.intel.com/products/server/chipsets/3400-3420/3400-3420-overview.…
and USB ID 8087:0020) and poor performance of USB soundcards? I've come
across two separate forum topics about it:
http://www.linuxmusicians.com/viewtopic.php?f=4&t=2588&st=0&sk=…
http://ubuntuforums.org/showthread.php?t=806730&page=4
The user on the LinuxMusicians forum could acknowledge that with Windows
he had the same performance issues so it's not Linux related but I just
wanted to know if anyone else encountered this phenomenon.
Best,
Jeremy
13 Jun
13 Jun
3:24 p.m.
Jeremy Jongepier wrote:
Does anybody know if there is any relationship between
the Intel Rate
Matching Hub and poor performance of USB soundcards?
The "Rate Matching" behaves just like a normal USB hub; this design
choice does not introduce any problems by itself.
However, the USB controllers in these chipsets (5 and 3400 series) are
just plain buggy; the bug list ("specification update") says:
| 6. Intel® 5 Series Chipset and Intel® 3400 Series Chipset Full-Speed
| USB Isochronous Packet Truncation
|
| Problem: Full-Speed isochronous-out transactions with multi-frame
| packets may be truncated, in the presence of Full or Low-Speed USB
| asynchronous transactions.
| • For this to occur, two devices, one performing Full-Speed
| isochronous-out transactions and one performing asynchronous
| transactions must be connected to the same USB controller
| (Ports 0-7 and 8-13).
|
| Implication: In the case of a USB audio device this issue may result
| in no audible impact or audible artifacts such as pops and clicks.
|
| Note:
| • High-Speed and Low-Speed USB devices are not impacted by this issue.
| • Only devices supporting Full-Speed isochronous-out transactions that
| Intel is aware of are audio devices, such as sound adapters,
| speakers, and headphones.
| • Intel has only observed the issue when a Full-Speed audio devices
| and Full-Speed USB web camera are connected to the same USB
| controller.
|
| Workaround: None.
| Status: Fixed
(that is, fixed in chip revision B3)
Regards,
Clemens
14 Jun
14 Jun
9:55 a.m.
On 06/13/2010 03:24 PM, Clemens Ladisch wrote:
Jeremy Jongepier wrote:
Hello Clemens,
Thanks for the info! That's a real bummer for those who acquired a
machine with these chipsets and want to use it with a USB soundcard :(
Case closed, thanks again.
Best,
Jeremy
Does anybody know if there is any relationship
between the Intel Rate
Matching Hub and poor performance of USB soundcards?
The "Rate Matching" behaves just like a normal USB hub; this design
choice does not introduce any problems by itself.
However, the USB controllers in these chipsets (5 and 3400 series) are
just plain buggy; the bug list ("specification update") says:
| 6. Intel® 5 Series Chipset and Intel® 3400 Series Chipset Full-Speed
| USB Isochronous Packet Truncation
|
| Problem: Full-Speed isochronous-out transactions with multi-frame
| packets may be truncated, in the presence of Full or Low-Speed USB
| asynchronous transactions.
| • For this to occur, two devices, one performing Full-Speed
| isochronous-out transactions and one performing asynchronous
| transactions must be connected to the same USB controller
| (Ports 0-7 and 8-13).
|
| Implication: In the case of a USB audio device this issue may result
| in no audible impact or audible artifacts such as pops and clicks.
|
| Note:
| • High-Speed and Low-Speed USB devices are not impacted by this issue.
| • Only devices supporting Full-Speed isochronous-out transactions that
| Intel is aware of are audio devices, such as sound adapters,
| speakers, and headphones.
| • Intel has only observed the issue when a Full-Speed audio devices
| and Full-Speed USB web camera are connected to the same USB
| controller.
|
| Workaround: None.
| Status: Fixed
(that is, fixed in chip revision B3)
Regards,
Clemens
5311
days inactive
5313
days old
linux-audio-user@lists.linuxaudio.org
2 comments
2 participants
participants (2)
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Clemens Ladisch -
Jeremy Jongepier