HDHomeRun tuners not being found

II have 2 HDHomeRun US tuners which my plex server can never find, even when I manually enter addresses.
device details: HDHomeRun DUAL ModelNumber:HDHR3-S Legacy:1 FirmwareName:hdhomerun3_atsc FirmwareVersion:20170930
(which is the latest firmware)
Plex server version is 1.9.2.4285, running on FreeNAS 9.10.

I’ve duplicated this problem with multiple “plex plugin” installs. The problem exists in all cases.

I’ve been using these tuners for years with MythTV so they work fine and are updated with latest firmware as mentioned above.

The plex logs show these errors:
DEBUG - Request: [192.168.1.107:55679 (Subnet)] POST /media/grabbers/tv.plex.grabbers.hdhomerun/devices?uri=192.168.1.125 (5 live) GZIP Signed-in Token (xxx)
DEBUG - DVR:Grabber: Checking device URI http://192.168.1.125
DEBUG - HTTP requesting GET http://192.168.1.125/discover.json
DEBUG - HTTP 200 response from GET http://192.168.1.125/discover.json
DEBUG - HTTP requesting GET http://192.168.1.125/capability
DEBUG - HTTP 404 response from GET http://192.168.1.125/capability
ERROR - DVR:Grabber: No tuner key exists for device, couldn’t obtain device status.
DEBUG - Completed: [192.168.1.107:55679] 404 POST /media/grabbers/tv.plex.grabbers.hdhomerun/devices?uri=192.168.1.125 (5 live) GZIP 217ms 452 bytes (pipelined: 1)
DEBUG - handleStreamRead code 2: End of file

Anyone have a clue how to solve this issue?

Thanks,
Tim

Is MythTV still running, or anything else that might be holding onto the HDHRs?
I found OLD post ‘dual isn’t supported’, BUT, I know Plex has updated to ‘all models’ in the time since the original first post I found was made. However, as of end of last month, someone did say make sure nothing else is using the HDHR.

Once you’ve answered that question ‘absolutely not, or not any longer’, you’re likely out of my scope of support. I know nothing of FreeNAS and it’s methods regarding tuner access.

It’s obvious Plex sees the tuner, it gets a 200 response from discover.json.
I’m not fully aware what that " DVR:Grabber: No tuner key exists for device" error means, but it could mean ‘no access to the tuner because some other app has it locked’

I don’t run freenas so not sure about how to configure Plex on freenas but have seen other posts regarding issues with Plex running in freenas or freebsd not discovering HDHR devices.

Do you have vimage turned on? There is a thread on the Plex forums discussing this as well as a freenas forum thread: https://forums.freenas.org/index.php?threads/plex-jail-and-vimage.54034/

Do you have a firewall turned on? There is an older discussion thread (https://forums.plex.tv/discussion/263750/silicondust-hdhomerun-tuners/p2) in which the firewall was causing an issue with one user configuring. But not sure if they were running on freenas.

Outside of these options I don’t have much else.