In the Virtual Service Image with a transaction that contains a JSON response, select Tree View and then set it back to Text View.
The JSON response will have escape characters that were added automatically.
Below images show how to reproduce this behavior:
In the image we can see the response does not contain the escape character:
<Please see attached file for image>
Change the view from Text View to Tree View:
<Please see attached file for image>
The Tree View:
<Please see attached file for image>
Change the View back to Text View:
<Please see attached file for image>
Notice the escape characters were added to the response:
<Please see attached file for image>
We may have a patch to address your issue. Please open a support ticket and reference DE296676.
We will be happy to provide you the patch if it matches your issue.
This issue does not happen with DevTest on release 10.1.