I have a pli image and I'm not sure if this will work for you.
Make a file "/var/etc/init" and put inside it:
Code:
{
sleep 20
wget -O /dev/null http://127.0.0.1/cgi-bin/admin?command=standby >/dev/null
} &
If that doesn't work, first make sure that wget works on the command line. Browse the files at /tuxbox /config/enigma and see if you can figure out an alternative. Maybe a remote control code?
Browse files at /etc/init.d or rc.d and figure out what it does at bootup and if it reads anything from the writable /var file system