My current setup:
Rpi 4 with Latest version of Tvheadend on Libreelec, using Pi's Tv head. Configured to use Pass streaming profile
Nvidia Shield using PVR Live application to pull in TV channels into Live Channels app.
Some HD channels (BBC 1 or ITV) will sometimes sit on loading and wont display, i can see a live subscription for that particular channel on TVheadend server with number for Input/output changing. Appears to happen with channels that broadcast 5.1 sounds for what i have gathered.
Tried a few different applications that pull channels into Live channels and same outcome, playing a problematic channels on vlc works however.
I am based in UK if that helps.
Any help if highly appreciated.