http://sn.1w6.org/file/mk-20141228T182413-7mg3sef.html

@lnxw48 thanks - these are good suggestions. The weird thing is, it seemed to deteriorate, first not being recognized intermittently, then only after hard reboot (but not as "replacement" for mouse or dongle), and today not recognized at all. All this in either port: I have two, one USB 2, one USB 3.0. Also, while it was still recognized, it was detected as "music player" - which it was not - but I could still use and write any files. There have been a lot of updates lately, so the 'deteriorate' may have something to do with that.