Would that be :
Frequency : 11428
Polarization : H
Sym rate : 27500
If that's it then it's not in the built-in muxes list, but I did add it manually and I tried playing it, I just get an error in VLC, it fails. It also shows as FAIL in tvheadend.
Log from tvheadend :
2021-03-08 15:15:49.552 [ INFO] subscription: 0480: "HTTP" unsubscribing, hostname="172.21.2.2", client="VLC/3.0.11 LibVLC/3.0.11"
2021-03-08 15:15:49.568 [ INFO] http: 172.21.2.2: using ticket ad70df9e617967fd901e2b58c13bd3df5989b73d for /stream/mux/3473db7e9793bb1146b55e248dfeb939
2021-03-08 15:15:49.568 [ INFO] mpegts: 11428H in Freesat - tuning on SAT>IP DVB-S Tuner #2 (172.21.3.175@UDP)
2021-03-08 15:15:49.568 [ INFO] subscription: 0484: "HTTP" subscribing to mux "11428H", weight: 10, adapter: "SAT>IP DVB-S Tuner #2 (172.21.3.175@UDP)", network: "Freesat", service: "Raw PID Subscription", hostname="172.21.2.2", client="VLC/3.0.11 LibVLC/3.0.11"
2021-03-08 15:15:59.568 [WARNING] subscription: 0484: service instance is bad, reason: No input detected
Error in VLC :
Your input can't be opened:
VLC is unable to open the MRL 'http://172.22.1.22:9981/stream/mux/3473db7e9793bb1146b55e248dfeb939?ticket=ad70df9e617967fd901e2b58c13bd3df5989b73d'. Check the log for details.
I left the two last boxes as AUTO, not sure if that could cause an issue. I did try a few settings in there too at one point but I never got it to work.
Note that playing a "working" mux like 12110H in vlc does not result in an error like that, it just displays nothing but doesn't error out like with 11428H.