RM 2.1 Standard sorting by title - Change between ascending and descending

[webmasterxl]

At the moment, if I set the standard sorting order in the resource manager to "title", the resources will be ordered by the title in an ascending manner. However, it is needed in a descending manner. I know that there isn't a setting in the backend to change this.

However, could anyone tell me, in which file I could change the code and how to change it in order to achieve the mentioned result?

Thanks in advance

webmasterxl