My Linux printer was scaling down 4x times each printout, except ones from “document viewer”. Turned out that default option “Pages per sheet” in CUPS was reset to 4.
In order to set default value of “Pages per sheet” in CUPS to 1:
1)Stop cups: /etc/init.d/cups stop
2)edit file /etc/cups/printers.conf and set
Option number-up 1
3)Start cups: /etc/init.d/cups start