Just to confirm, have you checked "Notify subscribers" under advanced settings while uploading videos? Also, have your subs reported that they are not getting notification? Let us know and we'll take a look!
We're here to help. Make sure that you've selected 'Notify subscribers' under 'Advanced settings'. Also double check if your subs have *all* notifications enabled and not the 'occasional' option. Also, your subs can check their notification settings: https://goo.gl/giVA8o