Problem with Doctrine Entity Class

Hi,
I am using Codeigniter 3.0 along with Doctrine ORM for several projects. I am going through the database first approach and then auto generate Entity and Proxy Classes. Recently I am facing a problem, whenever I send a request I get the entire Entity classes printed on the screen. If I manually delete the existing Entity classes (application/models/Entities/User.php, application/models/Entities/User.php~) and regenerate them, then the problem goes off for some time and again after few days I face the same problem. No idea what exactly triggers this error. Please advise.

Thanks in advance.

Regards,
Biswajit