Unit test cases working on vs 2013 but failure in vs 2015 enterprise edition

Hi Experts,

I have 400+ unit test cases which are working properly in vs 2013 after build solution. But when other developer take clone from git and open it in vs 2015 then run all test cases there are randomly few test cases are passed and other are failed. All test cases passed in vs 2013 but with vs 2015 few of them (e.g. 10 or 11) test cases passed and then other all are become failed.

Note : At every time in VS 2015 only 10 random test cases are passed and other are failed.

So is this any permission issue in Vs 2015?

Thanks,

Jack