Sorry for the bump but I had a similar issue. I had the same problem for a fairly large document. Another document however, worked fine but my large document did not.
I tried deleting all the generated files e.g. .aux, .bbl etc and then recompiling. This did not fix the problem.
I also tried resetting my texstudio profile by making a backup of my original profile and then opening texstudio again. This creates then a new profile. Again, this did not solve the problem.
I discovered the problem in my case was with the package:
Once I removed that, I was able to use the "go to source" function correctly. If you guys are having similar issues, where the "go to source" function still works correctly with other documents, I suggest there may exist some compatibility issue with the packages you are using in the problematic document.