AW: Strange behaviour of D-Link DUB-1312 USB 3.0 Adapters

["Schmid, Carsten" <Carsten_Schmid@mentor.com>]

>>> Plugging them into the same port (!) on my device one of them is
>>> recognized as SuperSpeed, the other as high speed ???
>>> (working on 4.14.129 LTS)
>>>
>>> From dmesg, the "faulty" one:
>>> [  530.585871] usb 1-2: new high-speed USB device number 4 using
>>> xhci_hcd   <<<<<<<<< HUH ????
>>>
>> XHCI is not like EHCI. It needs no companion controller, as it serves
>> all speeds.
>>
>> This is on a lower layer than ax88179. This comes from xhci_hcd.
>> Is this a regression?
>>
> I don't think its a regression.
>
I can see the same on a 4.14.102.

Next observation:
After some - long - time (> 15 minutes) a hanging ping
says:
ping: sendto: Network is unreachable

After this, without doing anything, i can start ping again
and it works:

$:~# ping 134.86.56.80
PING 134.86.56.80 (134.86.56.80): 56 data bytes
ping: sendto: Network is unreachable
$:~# ping 134.86.56.80
PING 134.86.56.80 (134.86.56.80): 56 data bytes
64 bytes from 134.86.56.80: seq=0 ttl=63 time=3.206 ms
64 bytes from 134.86.56.80: seq=1 ttl=63 time=0.662 ms

Looks like a higher rate of transfers causes a stall or retries
or whatever - but without any message i'm lost.
I can reproduce this 100%.

Someone there who has any advice what i can do to
track this down?

Best regards
Carsten