Autoclean up - Cleaning up download que even though its set to 0

its started a few versions back. i just assumed it had defaulted to something after an update
the download que is automatically cleaned up but the par2 isn't until i click cleanup
i tried turning it on and off and setting to 10 mins but it always cleans up
i turned off all "import x as paused options" to get the par files is that causing this

any ideas cheers