Was having trouble scanning for channels. I just replaced a HDHomeRun Extend with an older HDHomeRun Dual. I couldn't get it working. It was having issues scanning for channels. It would find a whole bunch as it was scanning, but after a few minutes at 100%, it would go back and say 0 channels found.
The http://my.hdhomerun.com/ wouldn't load at all.
I downloaded the crappy Silicon Dust software, it found channels in the setup utility, and would tune to them just fine in VLC. But the iPhone App or Microsoft Windows Store app wouldnt do anything.
Finally found the problem: I recently installed Snort service on my PFSense router. It was blocking all sorts of traffic. I removed the blocks, and the Channels App is finding channels now, and the WebUI of the Synology DVR is showing it found channels. http://my.hdhomerun.com/ is also working.
Just an FYI if anyone is having issues Scanning or channels; your router may be blocking the traffic.
Maybe a feature request: there was no error I could see, nor was there any error in the log.