Arc starts always with the same album

Since I have to walk our dog every day I started to become a heavy user of ROON arc! Glad to have this piece of software running on my iPhone.
Having around 6000 Tracks of Bob Dylan (all the offical albums and a lot of bootlegs) it is a good way to “work thru” this maqssive amount of music.
I alway start arc and select “artist: Bob Dylan” and let arc make the choices. It comes out that it is going to be a good mixture of old and new, live & studio music.
There are two “problems”:

  1. Almost every time arc starts with a track form “highway 61” This is really a great album

    But there should be a chance of starting with another album!
  2. After a while, about an hour or so, arc suddenly changes the selection, jumping from Bob Dylan to ABBA, (Konstantin Wecker (a german singer/songwriter), Allan Tylor and so on. Still having a lot of the 6000 tracks never ever played, there is no reason to change the selection.