Scarlett 18i20 Ubuntu 16.04 qjackctl problems

[Musicmaker]

Installed the standard Ubuntu 16.04 (on a test disk). Then from the software center qjackctl. (selected real-time support)
Result: Qjackctl most often does not start. Either, the qjackctl screen goes black and freezes or there are DBUS errors. Device selected is "USB".
Disabling realtime does not change thus. Disabling DBUS does not help as well.
When qjackctl does start, the 18i20 shows up as a Multi-channel audio interface and the test properties show the left/back/subwoofer etc..speakers.

I always upgrade to the latest Ubuntu and there the 18i20 always showed up as a stereo device. Never had much issues with the 18i20 until now (on the same machine). Something must have changed. Could not figure out yet the condition for starting and not starting of qjackctl.
Not upgrading to 16.04 (yet) Staying with 15.10.

[Musicmaker]

More audio card problems in 16.04, Also with the Presonus 1818VSL, 22VSL and Scarlett 2i2. Two previously working USB families (Focursrite Scarlett & Presonic audiovox) on Linux are having problems. https://bugs.launchpad.net/ubuntu/+sour ... ug/1574079