Going crazy with error that only occurs after build.

Hi. I have a working game that run just fine for two years. I have lot of builds working flawless, but yesterday when I build it crashes.

Do not crash in "development build" or the editor. I try undo everything I have done since last build but nothing works.

I have the last backup and the build with that file works just fine, but I have made a lot of work in the last week.

Sometimes it crash on load sometimes after some seconds.

Here the STACK look like physx but I can't figure out why.

Thanks in advance.

 

When it crashes after some seconds it look like this

 

I found the problem. Is a particle system, it work fine in editor but in build crashes. It has a different material that the others. Probably a bug. 6 working hours to find a damn bugged particle system