Hello,
there is maybe a bug in the screensaver scanning mode.
After the scan is finished (voice: scan complete) the scanner restarts again and aga…and…
in 4.8 it stopped and was just a screensaver.
am i the only one who noticed this behaviour?
daaf 
Scan computer / Scan now / Screen saver scan / More details / Settings / Screen saver / Loop scanning
(Provided you have the option “Show special scans in avast! user interface” checked in avast! settings.)
The same option existed in avast! 4.8… maybe the default was different, don’t know.
WHOOPS :-[ Duh. 
can’t remeber i have set it this way.
thanks
daaf