US (ATSC) frequencies

live in the Tampabay area of Florida USA. I have a Silicon Dust HDHR5-2US. My HTPC is running Libreelec which used TVHeadEnd 4.2.7. In general the quality of the received TV signal on the HTPC is poor. I also have a Channel Master CM7000-PAL which performs very well even when the HTPC is unwatchable. Both are feed from the same antenna and the same coax.

My question concerns the frequencies assigned to the various muxes. For example:

Call Name Virtual Real Band Direction Distance Mux TVH RF HDHR

WFTS-HD abc ABC 28.1 17 UHF 188.57° 6.05 mi 491.028 488.31 491.000

According to some information I found, RF channel 17 has:

Lower Edge Video Carrier ASTC Pilot Audio Carrier Upper edge

488 489.25 488.31 493.75 494

Center frequency is 491.00, however the mux has a frequency of 491.028. In general all of the muxes are like this. Should the mux frequencies be changed to x.000?

I found that there is a difference in frequencies reported by the HDHomerun app on my windows computer between when I use the SiliconDust supplied viewer and when I used my HTPC. The HTPC as I thought is 28+ KHZ off center frequency.

So I dove deep and modified an existing ATSC pre-defined mux file with center frequencies change to match SiliconDust. I re-scanned the muxes and services. and from the TvHeadEnd web page all looks good. However now Kodi is not seeing the TvHeadEnd server, TV is not listed on the main menu. Any ideas why TV is now not showing up?