WWW Class silent crach

I am working on an app that collect cards, to save space i use thumbnails in the app and download the bigger images when users views a card.

Everything worked fine until one day when i walked in the office and the WWW class start to halt the whole engine. I cant minimize move or focus the editor after the crash and the Task Manager do not report it as "Not responding". (Most likely stuck in the yield in some weird way)

Some images seems to work and i have tested the biggest (1.1MB) size images and the smallest (400KB) and they both work. I have changed the server code to accept get just to try too see if i could get the images to show in the browser and it all works fine.

i have tried with both

 yield return www;

and

 while(!www.isDone)
 {
 yield return new WaitForEndFrame();
 }

But non of them stop the silent crashing.

I have tested to add Debug.Log(www.bytesDownloaded); and i get to around half the image size before it crash.

I have also compiled the project to an Android and tried it there, but the crashes happens but on different images than in the editor. Clarification: If image A crash the editor and image B did not, on my device, the app crash (but no crash report) at image B and not A.

Anyone know how to fix this issue or is it an engine bug?