On 04/19/2014 08:21 AM, Len Ovens wrote:
My USB2 Canoscan scanner doesn't work on my Intel laptop's USB ports at
all; either 2 or 3.
My USB 1.1 (UCA-202) audio card works fine on Intel USB3 ports.
One issue that I think may complicate audio things on modern laptops is
that the built-in webcams may also be connected via USB. (Such is true
on my laptop, which uses an Intel motherboard.)
> If USB3.1 has a new plug format, it will be usb3 only and this may force
My card has never worked well when plugged into a USB2 hub that connects
to a USB2 port on the laptop. Even before USB3.
I think I saw a comment in the Intel USB3 driver code that the USB3
standard doesn't propagate device resets down the chain. So if you have
an external hub attached and the onboard USB3 hub is reset, the external
hub is not informed for the reset. So if your audio card is hanging off
an external hub, it sounds to me like it would never get a reset signal
unless you power cycle the hub it's attached to?
> I had not heard of the insertion count thing before. That is good to
I don't know about the insertion count thing. I don't know if Linux does
the same thing, but Windows is notorious for storing a configuration for
a removable device, and adamantly reusing that configuration even if the
configuration is broken. I've seen that mentioned as a frequent cause of
problems with HP USB multifunction devices and some USB NICs.
David W. Jones
authenticity, honesty, community
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