Plex unable to see HDHomeRun

I have a Plex server (v1.8.0.4109) running on a QNAP NAS (TVS-671, if that changes anything). I’ve just purchased a HDHomeRun and have it connected to my network.
I’ve set the IP address for the HomeRun to a manual address so it doesn’t change. I am log into its web interface with both the IP address and via ‘http://my.hdhomerun.com’.

I’ve followed the instructions from the Plex website and gone to ‘Settings -> Server -> Live TV & DVR (Beta)’ and tried to setup the HomeRun however it keeps searching. I’ve tried adding the IP address manually however it fails and says it can not connect.

Not sure where I have gone wrong, any ideas?

Do you have a firewall running on your NAS? If so, disable it temporary to see if it is the culprit.

Also have seen other threads on the forum where the HDHR was in a different subnet than the PMS Server. HDHR needs to be on same subnet as the server.

@rouq said:
Do you have a firewall running on your NAS? If so, disable it temporary to see if it is the culprit.
Not that causing it

@johnm_ColaSC said:
Also have seen other threads on the forum where the HDHR was in a different subnet than the PMS Server. HDHR needs to be on same subnet as the server.
On the same subnet 255.255.255.0.

Its something on the NAS / PMS on there as I’ve installed PMS on my MacBook and it connect without any issues.

I read in another thread that udp port 65001 must be opened in the firewall for discovery to work. Hope this will help.