Comment # 15 on bug 1017610 from Michael Andres

(In reply to Ladislav Slez�k from comment #12)
> Michael, any idea why this correct URL:
> ...
> Is tuned into invalid one here???

And only if an USB drive is in use? 
Well, one line in the log actually caught my eye:

> 2017-01-04 06:10:22 <1> install(3179) 
> [Pkg] Source_Create.cc(createManagedSource):158
> Original URL: 
> cd:///?devices=/dev/disk/by-id/usb-TSSTcorp_CDDVDW_SE-208AB_RL6X853-0:0, 
> product directory: ./
>                   ^^^

You are printing a zypp::Pathname here. Pathnames are normalized and do not
contain trailing '/'es. What you are printing here is a relative pathname
(./path) with an invisible name (but it's not an empty string):

  Pathname("")   --> ""
  Pathname(" ")  --> "./ "

The product directory looks fishy to me.