Image file base url missing

After bulk running my media library through the wp smush it plugin,
all the media file url’s were incomplete, the base url seems to have gone missing.

If you look at the media, it will say
http:///wp-content/uploads/2012/08/blabla.png

I have deleted the plugin, but the damage seems ‘permanent’.
With new images I upload it has the same problem.

I have a hinch it is database related but I can’t seem to find where to edit the data to fix it.

Can someone please point me to a solution to fix this issue?

After days of sweating and searching your help is much appreciated,
many thanks!