When visiting a domain before visiting a subdomain with a directory, typing in that subdomain with http:// or without any protocol causes it to go to the main domain instead of the subdomain.  I can type https:// and that immediately resolves the issue.

Possibly DNS related.  I've attached a video of the issue.

Chrome Version       : 50.0.2661.94
Other browsers tested:
     Safari: not tested
    Firefox: OK
         IE: OK

What steps will reproduce the problem?
(1) Go to domain.com initially (get dns)
(2) Go to subdomain.domain.com/directory

What is the expected result?
subdomain.domain.com/directory page opens


What happens instead?
domain.com/directory 404 opens