[opensuse-factory] Problems reading Video DVDs

Hi, For a few month now my OpenSUSE Tumbleweed system (last checked on 20190902) has more and more problems reading Video DVDs. For some time I was able to read the first layer of a double layer DVD, and I blamed and changed my DVD drive (twice). But now I am able to read only about 1GB from the the disk. Out of desperation I even set the region code for my drive, which I did not do for 12 years. libdvdcss2 is able to determine the first two keys for a given disk only. Is this a problem for me only, or could there be changes in libraries or kernel leading to this problem? Kind regards Berthold