Your 10 mins, might be a memory problem.
I am not using ffmpeg from libreelec. I've made a ffmpeg compilation with omx serving nginx server for live web transcoding of recordings - I might share it in the forum but I do not believe that is the issue.
-g 100 is the GOP length. 100 is recommended for mpeg streams.
-af "aresample=async=1:first_pts=0", helps audio resampling when there are interruptions in tv reception and solving audio de-syncs.
-bufsize 2048k increases the buffer size to help again handling interruptions in reception.
These had been very helpfull for me in receiving steady streams.
- For your tests I suggest you use an unencrypted channel.
- Also confirm you have a good cable connection (of course).
- And depending in your device, as I have a Raspberry Pi4 with 4GB, I have dedicated 512 KB to the GPU, which has been helpfull in timeshift buffering and fast-forward and rewiding recordings (gpu_mem=512 in /flash/config.txt)
- About timeshift, i only use RAM for timeshift, never disk, which also increases stability, as less disk access when watching tv.