Re: Disconnect/connect usb ports

[Swift Griggs <swiftgriggs%gmail.com@localhost>]

On Thu, 18 Feb 2016, Jose Luis Rodriguez Garcia wrote:
> The problem is very random. As you can suppose. Neither my pc ( a 
> nettop) or my lapto have ground.

I've had similar problems to the ones you and Felix describe. I was using 
a USB audio device with a fancy D/A converter. It'd get reset or stutter 
ever time I'd use my KVM. My KVM had a USB port that would get swapped 
between whatever systems it was currently connected to. That was causing 
some kind of surge or inrush that was causing the whole bus to reset. I 
also noticed that wasn't the only thing that would do it. Just about any 
power or USB related event would cause bus-resets.

The problems were specific to that system and to NetBSD running on it. It 
was using an AMD USB chip, too. I've had more problems from those versus 
Intel. Until I swapped out the system about four months ago, the only way 
I could use that little Brown-Burr USB audio device was to put it on a USB 
hub with it's own discrete power supply. I got even more paranoid and put 
the power adapter on a battery backed up line conditioner, too. I got some 
nice recordings after that.

Thanks,
  Swift