xscreensaver problem

[Pierre Frenkiel]

hi,
I have now a big problem with xscreensaver.
Up to yesterday, it worked perfectly, but I had to re-install Debian
on my PC, and now if fails
when I run "xscreensaver" I get:
   xscreensaver-systemd: 13:59:54: user bus connection failed: No medium found
If I run "xscreensaver-demo", I get "Segmentation fault"
I was unable to find what changes from my previous install to the new one
can explain that.
Has anybody an idea?
best regards,

Pierre Frenkiel