Installing apps without permission

[AC Question]

I have a new archos phone running android. I have AVG, kapersky and malware bytes. Every night the 'allow installation from unknown sources' slides itself on, and at least one random app installs itself without any warning. I have been turning the setting straight off and uninstalling​ the apps but it keeps happening. Advice please? Thanks

 

[belodion]

Does it persist in Safe Mode?