S400 focus issue and ISO auto.. help

[JDRock]

Hi,
I just got my S400 recently, but seems like the focus is giving me probelms. The little square box in the LCD appear in orange color and the lower orange light indicator blinking to indicate unable to focus most of the time.
I use the tripod to fous a same object, and I can only get the green box in the LCD and no light at the lower indicator 4 out of 10 times. Other than that it keeps telling me unable to focus to the same object.
Can anyone help me how to take a good photos with this small little toy as I also encounter the noise when I view in actual size on the PC. My setting is ISO auto. Do I need to set it to always ISO 50 or 100 ?
Thanks...

[stopbath]

Auto focus in your camera works by contrast, so focusing on a solid tone object won't work. You need a sharp contrast in tone.

Low light gives the camera much less data to work with to attain positive focus.

Try to focus in well lit areas, and on tone changes (edges)

As for video noise, Auto ISO will try to retain ISO 50, but will degrade into higher ISO's if it deems required. I would suggest setting it manually to ISO 50, then move to ISO 100 or higher when required (at your choice.)
Even at ISO 50, you'll get some noise on long exposures or underexposure (when you brighten the image.)