Nikon Coolscan LS40

If, by SOFT images you are referring to a scan that has the look of the soft-focus lenses they use for aging actresses, and the darks are over-run with a glow from the the lights, it's probably as simple as a dirty reflecting mirror.

If when facing the front of the machine there is a lens/scanner pointing directly at you, inside the machine, below the Magazine insertion hole.

Between you and that lens is a little 45° mirror that bounces the film's image to the lens.

That mirror, which faces away form you in a vertical orientation, will 'fog' over time from smoke and grime -- microscopic particles of dust -- settling on the mirror surface. It makes the light beams scatter, making pictures look like this:

<img src="http://www.darrowart.com/other/forums/sample_foggy.jpg">

But with the instructions (for a similar model) found here, you can easily clean the mirror (I used windex and a cotton ball after removing the mirror.

Now I get scans that look like this:

<img src="http://www.darrowart.com/other/forums/truck-sample.jpg">

Well it is not a self servicable item. So you have a decision. If the cost is 50% of a new one- why not have a go. I personally do not think it is dirty This is a firm ware malfunction and will as they say mean a replacement of the item. Get the next one - Not a Nikon IMHO these dedicated film scanners are now a bit old hat- a high end flatbed will do as good a job for most general purpose work. After all digitising means -setting a resolution suitable for a screen and or printing- neither exactly demanding for quality.