Media Server No Longer Working Correctly - NETGEAR Nighthawk X4 AC2350

Hello forum,

I have a NETGEAR Nighthawk X4 AC2350 that has historically always played .mkv files easily from my Western Digital USB connected hard drive, connected to the router and using the Media Server function on the router.  My Samsung TVs could easily see the hard drive and play through the network.  Now though, sometimes my TVs can't even see the hard drive, whereas other times they can only see title from alphanumerics down to those whose title starts with "H," nothing further.  I've tried installing the VLC media player app and that can sometimes see the drive, but can't play anything from the drive.

Using my desktop connected to the local network, I am able to connect to the drive and play the videos that way, but still cannot get them to work via any of my smart TVs or the VLC app through Firesticks or smart TV directly.  

Can anyone help me figure out where my issue is?  We miss watching our digitized movies.