shadow problems

in my attached pic it shows the soft shadows in my project working OK, they are on maximum resolution and the max distance is only 50 with a cascade of 4. but i get the odd parts (circled in red on the picture). I can not work out what is causing it or how to solve it. Basically the wall will cast a shadow but where the wall meets another wall or the floor the shadow seems to "come away" from the wall casting the shadow. This seems to happen a lot on a lot of the FBX's i have created and imported.

I am using Indy Unity and there is only 1 light casting shadows. Anyone got any ideas, please? this is really doing my head in! Or is it a case that if i want good shadows i have to get Unity Pro, but even then is there any garentee it will draw properly?